FINDING ENGAGING AND ATTRACTIVE APP TYPES WORTH INVESTING IN.

The aim of this project is to identify app types that tend to attract more users and engagement by analyzing Datasets of Andoid and IOS mobile apps. The goal is to help our developers and company know which kind of apps are more profitable.

At the end we discovered that taking a popular book (perhaps a more recent book) and turning it into an app could be profitable for both the Google Play and the App Store markets.

Opening and Exploring the Data

In [2]:
from csv import reader

### Opening and reading the apple dataset ###
opened_file = open('AppleStore.csv')
read_file = reader(opened_file)

 #Transform read_file into a list of lists
apple_dataset = list(read_file)
apple_dataset_header = apple_dataset[0]
apple_dataset = apple_dataset[1:] # Omit the first row - it contains the headers


### Opening the google dataset ###
opened_file = open('googleplaystore.csv')
read_file = reader(opened_file)

 #Transform read_file into a list of lists
google_dataset = list(read_file)
google_dataset_header = google_dataset[0]
google_dataset = google_dataset[1:] # Omit the first row - it contains the headers
In [3]:
def explore_data(dataset, start, end, rows_and_columns=False):
    dataset_slice = dataset[start:end]
    for row in dataset_slice:
        print(row)
        print('\n') # adds a new (empty) line between rows
        
        
    if rows_and_columns:
        print('Number of rows:', len(dataset))
        print('Number of columns:', len(dataset[0]))
        

print(apple_dataset_header)
print('\n')
explore_data(apple_dataset, 0, 3, True)
['id', 'track_name', 'size_bytes', 'currency', 'price', 'rating_count_tot', 'rating_count_ver', 'user_rating', 'user_rating_ver', 'ver', 'cont_rating', 'prime_genre', 'sup_devices.num', 'ipadSc_urls.num', 'lang.num', 'vpp_lic']


['284882215', 'Facebook', '389879808', 'USD', '0.0', '2974676', '212', '3.5', '3.5', '95.0', '4+', 'Social Networking', '37', '1', '29', '1']


['389801252', 'Instagram', '113954816', 'USD', '0.0', '2161558', '1289', '4.5', '4.0', '10.23', '12+', 'Photo & Video', '37', '0', '29', '1']


['529479190', 'Clash of Clans', '116476928', 'USD', '0.0', '2130805', '579', '4.5', '4.5', '9.24.12', '9+', 'Games', '38', '5', '18', '1']


Number of rows: 7197
Number of columns: 16

Now, lets see what the google dataset gives us;

In [4]:
print(google_dataset_header)
print('\n')
explore_data(google_dataset, 0, 3, True)
['App', 'Category', 'Rating', 'Reviews', 'Size', 'Installs', 'Type', 'Price', 'Content Rating', 'Genres', 'Last Updated', 'Current Ver', 'Android Ver']


['Photo Editor & Candy Camera & Grid & ScrapBook', 'ART_AND_DESIGN', '4.1', '159', '19M', '10,000+', 'Free', '0', 'Everyone', 'Art & Design', 'January 7, 2018', '1.0.0', '4.0.3 and up']


['Coloring book moana', 'ART_AND_DESIGN', '3.9', '967', '14M', '500,000+', 'Free', '0', 'Everyone', 'Art & Design;Pretend Play', 'January 15, 2018', '2.0.0', '4.0.3 and up']


['U Launcher Lite – FREE Live Cool Themes, Hide Apps', 'ART_AND_DESIGN', '4.7', '87510', '8.7M', '5,000,000+', 'Free', '0', 'Everyone', 'Art & Design', 'August 1, 2018', '1.2.4', '4.0.3 and up']


Number of rows: 10841
Number of columns: 13

Data Cleaning - DELETING WRONG DATA

Based on observations and discussions we discoverd that an app in the google play store contains a missing value. We have to find the app and delete it from our dataset.

In [5]:
for row in google_dataset: 
    if len(row) != len(google_dataset_header):
        print(row)
        print(google_dataset.index(row))
['Life Made WI-Fi Touchscreen Photo Frame', '1.9', '19', '3.0M', '1,000+', 'Free', '0', 'Everyone', '', 'February 11, 2018', '1.0.19', '4.0 and up']
10472

DATA CLEANING: Based on the code above, we can see that row number 10472 has a missing value (12 VALUES INSTEAD OF 13) and hence will be deleted as shown below;

In [6]:
del google_dataset[10472]

DUPLICATE ENTRIES REMOVAL

Still on DATA CLEANING, We noticed lots of duplicate entries like the one below:

In [7]:
for app in google_dataset:
    name = app[0]
    if name == 'Instagram':
        print(app)
    
['Instagram', 'SOCIAL', '4.5', '66577313', 'Varies with device', '1,000,000,000+', 'Free', '0', 'Teen', 'Social', 'July 31, 2018', 'Varies with device', 'Varies with device']
['Instagram', 'SOCIAL', '4.5', '66577446', 'Varies with device', '1,000,000,000+', 'Free', '0', 'Teen', 'Social', 'July 31, 2018', 'Varies with device', 'Varies with device']
['Instagram', 'SOCIAL', '4.5', '66577313', 'Varies with device', '1,000,000,000+', 'Free', '0', 'Teen', 'Social', 'July 31, 2018', 'Varies with device', 'Varies with device']
['Instagram', 'SOCIAL', '4.5', '66509917', 'Varies with device', '1,000,000,000+', 'Free', '0', 'Teen', 'Social', 'July 31, 2018', 'Varies with device', 'Varies with device']

Lets count the number of duplicate entries/apps in our google play dataset.

In [8]:
unique_apps = []
duplicate_apps= []

for app in google_dataset:
    name = app[0]
    if name in unique_apps:
        duplicate_apps.append(name)
    else:
        unique_apps.append(name)
        
print('Number of duplicate apps:', len(duplicate_apps))
Number of duplicate apps: 1181

We wont remove these duplicates randomly. Looking at the duplicates in the Instagram app in the output of cell 7 above, the main difference happens on the fourth position of each row which corresponds to the number of reviews. The different numbers show the data was collected at different times.

The higher the number of reviews, the more recent the data should be. Rather than removing duplicates randomly, we'll retain the row with the highest number of reviews.

First, lets create a dictionary where each key is a unique app name, and the value is the highest number of reviews of that app.

In [9]:
reviews_max = {}
for app in google_dataset:
    name = app[0]
    n_reviews = float(app[3]) #In string format but now coverted to numbers
    
    if name in reviews_max and reviews_max[name] < n_reviews:
        reviews_max[name] = n_reviews
        
    elif name not in reviews_max:
        reviews_max[name] = n_reviews
    

Remember we have 1181 dulicate apps in the google dataset so our dictionary with unique apps (the reviews_max dictionary) is the difference between total apps and duplicate apps.

In [10]:
print('Unique apps:', len(google_dataset) - len (duplicate_apps))
print(len(reviews_max))
Unique apps: 9659
9659

Now lets use the reviews_max dictionary to create a new data set, which will have only one entry per app (and we only select the apps with the highest number of reviews)

In [11]:
google_clean = []
already_added = []

for app in google_dataset:
    name = app[0]
    n_reviews = float(app[3])
    
    
    if (reviews_max[name] == n_reviews) and (name not in already_added):
        google_clean.append(app)
        already_added.append(name) #Must be inside the if block 
    
    

Now lets explore the new data set and re-confirm the total numbrer of rows to be 9659.

In [12]:
explore_data(google_clean, 0, 3, True)
['Photo Editor & Candy Camera & Grid & ScrapBook', 'ART_AND_DESIGN', '4.1', '159', '19M', '10,000+', 'Free', '0', 'Everyone', 'Art & Design', 'January 7, 2018', '1.0.0', '4.0.3 and up']


['U Launcher Lite – FREE Live Cool Themes, Hide Apps', 'ART_AND_DESIGN', '4.7', '87510', '8.7M', '5,000,000+', 'Free', '0', 'Everyone', 'Art & Design', 'August 1, 2018', '1.2.4', '4.0.3 and up']


['Sketch - Draw & Paint', 'ART_AND_DESIGN', '4.5', '215644', '25M', '50,000,000+', 'Free', '0', 'Teen', 'Art & Design', 'June 8, 2018', 'Varies with device', '4.2 and up']


Number of rows: 9659
Number of columns: 13

Removing Non-English Apps

1

If you explore the data sets enough, you'll notice the names of some of the apps suggest they are not directed toward an English-speaking audience.

We're not interested in keeping these kind of apps, so we'll remove them. All these characters that are specific to English texts are encoded using the ASCII standard. Each ASCII character has a corresponding number between 0 and 127 associated with it.

We built this function below, and we use the built-in ord() function to find out the corresponding encoding number of each character.

In [13]:
def is_english(string):
    non_ascii = 0
    
    for character in string:
        if ord(character) > 127: #According to ASCII, all English xters are between 0-127#
            non_ascii += 1
            
    if non_ascii > 3:
        return False
    else:
        return True
        
print(is_english('Instagram'))
print(is_english('爱奇艺PPS -《欢乐颂2》电视剧热播'))
True
False

Function works fine. Now lets use is_english() function to filter out non-English apps from both datasets.

In [14]:
google_english = []
apple_english = []

for app in google_clean:
    name = app[0]
    if is_english(name):
        google_english.append(app)
        
for app in apple_dataset:
    name = app[1]
    if is_english(name):
        apple_english.append(app)
        
explore_data(google_english, 0, 3, True)
print('\n')
explore_data(apple_english, 0, 3, True)
['Photo Editor & Candy Camera & Grid & ScrapBook', 'ART_AND_DESIGN', '4.1', '159', '19M', '10,000+', 'Free', '0', 'Everyone', 'Art & Design', 'January 7, 2018', '1.0.0', '4.0.3 and up']


['U Launcher Lite – FREE Live Cool Themes, Hide Apps', 'ART_AND_DESIGN', '4.7', '87510', '8.7M', '5,000,000+', 'Free', '0', 'Everyone', 'Art & Design', 'August 1, 2018', '1.2.4', '4.0.3 and up']


['Sketch - Draw & Paint', 'ART_AND_DESIGN', '4.5', '215644', '25M', '50,000,000+', 'Free', '0', 'Teen', 'Art & Design', 'June 8, 2018', 'Varies with device', '4.2 and up']


Number of rows: 9614
Number of columns: 13


['284882215', 'Facebook', '389879808', 'USD', '0.0', '2974676', '212', '3.5', '3.5', '95.0', '4+', 'Social Networking', '37', '1', '29', '1']


['389801252', 'Instagram', '113954816', 'USD', '0.0', '2161558', '1289', '4.5', '4.0', '10.23', '12+', 'Photo & Video', '37', '0', '29', '1']


['529479190', 'Clash of Clans', '116476928', 'USD', '0.0', '2130805', '579', '4.5', '4.5', '9.24.12', '9+', 'Games', '38', '5', '18', '1']


Number of rows: 6183
Number of columns: 16

We can see that we're now left with 9614 Google play store apps and 6183 Apple iOS apps

Isolating the free apps

we only build apps that are free to download and install, and our main source of revenue consists of in-app ads. Our data sets contain both free and non-free apps, and we'll need to isolate only the free apps for our analysis. Below, we isolate the free apps for both data sets.

In [15]:
google_final = []
apple_final = []

for app in google_english:
    price = app[7]
    if price == '0':
        google_final.append(app)
        
for app in apple_english:
    price = app[4]
    if price == '0.0':
        apple_final.append(app)
        
print(len(google_final))
print(len(apple_final))
8864
3222

We're left with 8864 Google play store apps and 3222 Apple iOS apps, which should be enough for our analysis.

Most Common Apps by Genre 1:

As we mentioned in the introduction, our aim is to determine the kinds of apps that are likely to attract more users because our revenue is highly influenced by the number of people using our apps.

To minimize risks and overhead, our validation strategy for an app idea is comprised of three steps:

1. Build a minimal Android version of the app, and add it to Google Play.
2. If the app has a good response from users, we then develop it further.
3. If the app is profitable after six months, we also build an iOS version of the app and add it to the App Store.

Because our end goal is to add the app on both the App Store and Google Play, we need to find app profiles that are successful on both markets.

Let's begin the analysis by getting a sense of the most common genres for each market. For this, we'll build a frequency table for the prime_genre column of the App Store data set, and the Genres and Category columns of the Google Play data set.

2

We'll build two functions we can use to analyze the frequency tables:

  1. One function to generate frequency tables that show percentages
  2. Another function that we can use to display the percentages in a descending order
In [16]:
def freq_table(dataset, index):
    table = {}
    total = 0
    
    for row in dataset:
        total += 1
        value = row[index]
        if value in table:
            table[value] += 1
            
        else:
            table[value] = 1
            
    table_percentages = {}
    for key in table:
        percentage = (table[key] / total * 100)
        table_percentages[key] = percentage
    
    return table_percentages
    
    
def display_table(dataset, index):
    table = freq_table(dataset, index)
    table_display = []
    for key in table:
        key_val_as_tuple = (table[key], key)
        table_display.append(key_val_as_tuple)

    table_sorted = sorted(table_display, reverse = True) #sorted functon to arrange our values in ascending order so has to be reversed
    for entry in table_sorted:
        print(entry[1], ':', entry[0])
            
        

3

Now lets analyze or examine those selected columns of our datasets. we start with the prime_genre column of the App store dataset.

In [17]:
display_table(apple_final, -5 )
Games : 58.16263190564867
Entertainment : 7.883302296710118
Photo & Video : 4.9658597144630665
Education : 3.662321539416512
Social Networking : 3.2898820608317814
Shopping : 2.60707635009311
Utilities : 2.5139664804469275
Sports : 2.1415270018621975
Music : 2.0484171322160147
Health & Fitness : 2.0173805090006205
Productivity : 1.7380509000620732
Lifestyle : 1.5828677839851024
News : 1.3345747982619491
Travel : 1.2414649286157666
Finance : 1.1173184357541899
Weather : 0.8690254500310366
Food & Drink : 0.8069522036002483
Reference : 0.5586592178770949
Business : 0.5276225946617008
Book : 0.4345127250155183
Navigation : 0.186219739292365
Medical : 0.186219739292365
Catalogs : 0.12414649286157665

We can see from the percentages above for the English free apps in the App store dataset that 58% (more than half) are Games. Also almost 8% under entertainment and nearly 5% under photo & video.

This show that majority of English free apps are for fun (games, entertainment, photo & video, social networking, sports etc), while apps with practical purposes (education, shopping, utilities, productivity, lifestyle, etc.) are more rare. However, the fact that fun apps are the most numerous doesn't also imply that they also have the highest number of users — the demand might not be the same as the offer.

Let's continue by examining the Genres and Category columns of the Google Play data set (two columns which seem to be related)

In [18]:
display_table(google_final, 1) # Category
FAMILY : 18.907942238267147
GAME : 9.724729241877256
TOOLS : 8.461191335740072
BUSINESS : 4.591606498194946
LIFESTYLE : 3.9034296028880866
PRODUCTIVITY : 3.892148014440433
FINANCE : 3.7003610108303246
MEDICAL : 3.531137184115524
SPORTS : 3.395758122743682
PERSONALIZATION : 3.3167870036101084
COMMUNICATION : 3.2378158844765346
HEALTH_AND_FITNESS : 3.0798736462093865
PHOTOGRAPHY : 2.944494584837545
NEWS_AND_MAGAZINES : 2.7978339350180503
SOCIAL : 2.6624548736462095
TRAVEL_AND_LOCAL : 2.33528880866426
SHOPPING : 2.2450361010830324
BOOKS_AND_REFERENCE : 2.1435018050541514
DATING : 1.861462093862816
VIDEO_PLAYERS : 1.7937725631768955
MAPS_AND_NAVIGATION : 1.3989169675090252
FOOD_AND_DRINK : 1.2409747292418771
EDUCATION : 1.1620036101083033
ENTERTAINMENT : 0.9589350180505415
LIBRARIES_AND_DEMO : 0.9363718411552346
AUTO_AND_VEHICLES : 0.9250902527075812
HOUSE_AND_HOME : 0.8235559566787004
WEATHER : 0.8009927797833934
EVENTS : 0.7107400722021661
PARENTING : 0.6543321299638989
ART_AND_DESIGN : 0.6430505415162455
COMICS : 0.6204873646209386
BEAUTY : 0.5979241877256317

There seems to be a bit more balanced landscape of both practical and fun apps in Google play dataset than in app store dataset (For free English apps anyways).

Lets see what plays out with the genres column below.

In [19]:
display_table(google_final, -4) #genres
Tools : 8.449909747292418
Entertainment : 6.069494584837545
Education : 5.347472924187725
Business : 4.591606498194946
Productivity : 3.892148014440433
Lifestyle : 3.892148014440433
Finance : 3.7003610108303246
Medical : 3.531137184115524
Sports : 3.463447653429603
Personalization : 3.3167870036101084
Communication : 3.2378158844765346
Action : 3.1024368231046933
Health & Fitness : 3.0798736462093865
Photography : 2.944494584837545
News & Magazines : 2.7978339350180503
Social : 2.6624548736462095
Travel & Local : 2.3240072202166067
Shopping : 2.2450361010830324
Books & Reference : 2.1435018050541514
Simulation : 2.0419675090252705
Dating : 1.861462093862816
Arcade : 1.8501805054151623
Video Players & Editors : 1.7712093862815883
Casual : 1.7599277978339352
Maps & Navigation : 1.3989169675090252
Food & Drink : 1.2409747292418771
Puzzle : 1.128158844765343
Racing : 0.9927797833935018
Role Playing : 0.9363718411552346
Libraries & Demo : 0.9363718411552346
Auto & Vehicles : 0.9250902527075812
Strategy : 0.9138086642599278
House & Home : 0.8235559566787004
Weather : 0.8009927797833934
Events : 0.7107400722021661
Adventure : 0.6768953068592057
Comics : 0.6092057761732852
Beauty : 0.5979241877256317
Art & Design : 0.5979241877256317
Parenting : 0.4963898916967509
Card : 0.45126353790613716
Casino : 0.42870036101083037
Trivia : 0.41741877256317694
Educational;Education : 0.39485559566787
Board : 0.3835740072202166
Educational : 0.3722924187725632
Education;Education : 0.33844765342960287
Word : 0.2594765342960289
Casual;Pretend Play : 0.236913357400722
Music : 0.2030685920577617
Racing;Action & Adventure : 0.16922382671480143
Puzzle;Brain Games : 0.16922382671480143
Entertainment;Music & Video : 0.16922382671480143
Casual;Brain Games : 0.13537906137184114
Casual;Action & Adventure : 0.13537906137184114
Arcade;Action & Adventure : 0.12409747292418773
Action;Action & Adventure : 0.10153429602888085
Educational;Pretend Play : 0.09025270758122744
Simulation;Action & Adventure : 0.078971119133574
Parenting;Education : 0.078971119133574
Entertainment;Brain Games : 0.078971119133574
Board;Brain Games : 0.078971119133574
Parenting;Music & Video : 0.06768953068592057
Educational;Brain Games : 0.06768953068592057
Casual;Creativity : 0.06768953068592057
Art & Design;Creativity : 0.06768953068592057
Education;Pretend Play : 0.056407942238267145
Role Playing;Pretend Play : 0.04512635379061372
Education;Creativity : 0.04512635379061372
Role Playing;Action & Adventure : 0.033844765342960284
Puzzle;Action & Adventure : 0.033844765342960284
Entertainment;Creativity : 0.033844765342960284
Entertainment;Action & Adventure : 0.033844765342960284
Educational;Creativity : 0.033844765342960284
Educational;Action & Adventure : 0.033844765342960284
Education;Music & Video : 0.033844765342960284
Education;Brain Games : 0.033844765342960284
Education;Action & Adventure : 0.033844765342960284
Adventure;Action & Adventure : 0.033844765342960284
Video Players & Editors;Music & Video : 0.02256317689530686
Sports;Action & Adventure : 0.02256317689530686
Simulation;Pretend Play : 0.02256317689530686
Puzzle;Creativity : 0.02256317689530686
Music;Music & Video : 0.02256317689530686
Entertainment;Pretend Play : 0.02256317689530686
Casual;Education : 0.02256317689530686
Board;Action & Adventure : 0.02256317689530686
Video Players & Editors;Creativity : 0.01128158844765343
Trivia;Education : 0.01128158844765343
Travel & Local;Action & Adventure : 0.01128158844765343
Tools;Education : 0.01128158844765343
Strategy;Education : 0.01128158844765343
Strategy;Creativity : 0.01128158844765343
Strategy;Action & Adventure : 0.01128158844765343
Simulation;Education : 0.01128158844765343
Role Playing;Brain Games : 0.01128158844765343
Racing;Pretend Play : 0.01128158844765343
Puzzle;Education : 0.01128158844765343
Parenting;Brain Games : 0.01128158844765343
Music & Audio;Music & Video : 0.01128158844765343
Lifestyle;Pretend Play : 0.01128158844765343
Lifestyle;Education : 0.01128158844765343
Health & Fitness;Education : 0.01128158844765343
Health & Fitness;Action & Adventure : 0.01128158844765343
Entertainment;Education : 0.01128158844765343
Communication;Creativity : 0.01128158844765343
Comics;Creativity : 0.01128158844765343
Casual;Music & Video : 0.01128158844765343
Card;Action & Adventure : 0.01128158844765343
Books & Reference;Education : 0.01128158844765343
Art & Design;Pretend Play : 0.01128158844765343
Art & Design;Action & Adventure : 0.01128158844765343
Arcade;Pretend Play : 0.01128158844765343
Adventure;Education : 0.01128158844765343

Its now clear that the Google play store dataset has a better representation of practical apps than the App store dataset.

The difference between the Genres and the Category columns is not crystal clear, but one thing we can notice is that the Genres column is much more detailed/granular. We're only looking for the bigger picture at the moment, so we'll only work with the Category column moving forward.

Up to this point, we found that the App Store is dominated by apps designed for fun, while Google Play shows a more balanced landscape of both practical and for-fun apps. Now we'd like to get an idea about the kind of apps that have most users.

Most Popular Apps by Genre on the App Store

One way to find out what genres are the most popular (have the most users) is to calculate the average number of installs for each app genre. For the Google Play data set, we can find this information in the Installs column, but for the App Store data set this information is missing. As a workaround, we'll take the total number of user ratings as a proxy, which we can find in the rating_count_tot app.

Below, we calculate the average number of user ratings per app genre on the App Store:

In [20]:
genres_apple = freq_table(apple_final, -5)

for genre in genres_apple:
    total = 0
    len_genre = 0
    for app in apple_final:
        genre_app = app[-5]
        if genre_app == genre:
            n_ratings = float(app[5])
            total += n_ratings
            len_genre += 1
    avg_n_ratings = total / len_genre
    print(genre, ':', avg_n_ratings)
Social Networking : 71548.34905660378
Photo & Video : 28441.54375
Games : 22788.6696905016
Music : 57326.530303030304
Reference : 74942.11111111111
Health & Fitness : 23298.015384615384
Weather : 52279.892857142855
Utilities : 18684.456790123455
Travel : 28243.8
Shopping : 26919.690476190477
News : 21248.023255813954
Navigation : 86090.33333333333
Lifestyle : 16485.764705882353
Entertainment : 14029.830708661417
Food & Drink : 33333.92307692308
Sports : 23008.898550724636
Book : 39758.5
Finance : 31467.944444444445
Education : 7003.983050847458
Productivity : 21028.410714285714
Business : 7491.117647058823
Catalogs : 4004.0
Medical : 612.0

Looking at the above, NAVIGATION apps have the highest number of reviews on average. However, taking a closer look shows that these genres with highest number of reviews (navigation, music, social networking, reference etc) are influenced by a few very popular apps. For example;

In [21]:
for app in apple_final:
    if app[-5] == 'Reference':
        print(app[1], ':', app[5])
Bible : 985920
Dictionary.com Dictionary & Thesaurus : 200047
Dictionary.com Dictionary & Thesaurus for iPad : 54175
Google Translate : 26786
Muslim Pro: Ramadan 2017 Prayer Times, Azan, Quran : 18418
New Furniture Mods - Pocket Wiki & Game Tools for Minecraft PC Edition : 17588
Merriam-Webster Dictionary : 16849
Night Sky : 12122
City Maps for Minecraft PE - The Best Maps for Minecraft Pocket Edition (MCPE) : 8535
LUCKY BLOCK MOD ™ for Minecraft PC Edition - The Best Pocket Wiki & Mods Installer Tools : 4693
GUNS MODS for Minecraft PC Edition - Mods Tools : 1497
Guides for Pokémon GO - Pokemon GO News and Cheats : 826
WWDC : 762
Horror Maps for Minecraft PE - Download The Scariest Maps for Minecraft Pocket Edition (MCPE) Free : 718
VPN Express : 14
Real Bike Traffic Rider Virtual Reality Glasses : 8
教えて!goo : 0
Jishokun-Japanese English Dictionary & Translator : 0

We can see its actually the Bible and Dictionary.com which skew up the average rating.

Other genres that seem popular include weather, book, food and drink, or finance.One thing we could do is take another popular book and turn it into an app where we could add different features besides the raw version of the book. On top of that, we could also embed a dictionary within the app, so users don't need to exit our app to look up words in an external app.

This idea seems to fit well with the fact that the App Store is dominated by for-fun apps. This suggests the market might be a bit saturated with for-fun apps, which means a practical app might have more of a chance to stand out among the huge number of apps on the App Store.

Most Popular Apps by Genre on Google Play

For the Google Play market, we actually have data about the number of installs, so we should be able to get a clearer picture about genre popularity. However, the install numbers don't seem precise enough — we can see that most values are open-ended (100+, 1,000+, 5,000+, etc.):

In [22]:
categories_google = freq_table(google_final, 1)

for category in categories_google:
    total = 0
    len_category = 0
    for app in google_final:
        category_app = app[1]
        if category_app == category:            
            n_installs = app[5]
            n_installs = n_installs.replace(',', '') #removing the commas#
            n_installs = n_installs.replace('+', '') #removing the + signs#
            total += float(n_installs) #converting the strings to floats#
            len_category += 1
    avg_n_installs = total / len_category
    print(category, ':', avg_n_installs)
ART_AND_DESIGN : 1986335.0877192982
AUTO_AND_VEHICLES : 647317.8170731707
BEAUTY : 513151.88679245283
BOOKS_AND_REFERENCE : 8767811.894736841
BUSINESS : 1712290.1474201474
COMICS : 817657.2727272727
COMMUNICATION : 38456119.167247385
DATING : 854028.8303030303
EDUCATION : 1833495.145631068
ENTERTAINMENT : 11640705.88235294
EVENTS : 253542.22222222222
FINANCE : 1387692.475609756
FOOD_AND_DRINK : 1924897.7363636363
HEALTH_AND_FITNESS : 4188821.9853479853
HOUSE_AND_HOME : 1331540.5616438356
LIBRARIES_AND_DEMO : 638503.734939759
LIFESTYLE : 1437816.2687861272
GAME : 15588015.603248259
FAMILY : 3695641.8198090694
MEDICAL : 120550.61980830671
SOCIAL : 23253652.127118643
SHOPPING : 7036877.311557789
PHOTOGRAPHY : 17840110.40229885
SPORTS : 3638640.1428571427
TRAVEL_AND_LOCAL : 13984077.710144928
TOOLS : 10801391.298666667
PERSONALIZATION : 5201482.6122448975
PRODUCTIVITY : 16787331.344927534
PARENTING : 542603.6206896552
WEATHER : 5074486.197183099
VIDEO_PLAYERS : 24727872.452830188
NEWS_AND_MAGAZINES : 9549178.467741935
MAPS_AND_NAVIGATION : 4056941.7741935486

On average, communication apps have the most installs: 38,456,119. This number is heavily skewed up by a few apps that have over one billion installs (WhatsApp, Facebook Messenger, Skype, Google Chrome, Gmail, and Hangouts), and a few others with over 100 and 500 million installs.

We see the same pattern for the video players category, which is the runner-up with 24,727,872 installs. The market is dominated by apps like Youtube, Google Play Movies & TV, or MX Player. The pattern is repeated for social apps (where we have giants like Facebook, Instagram, Google+, etc.), photography apps (Google Photos and other popular photo editors), or productivity apps (Microsoft Word, Dropbox, Google Calendar, Evernote, etc.).

Again, the main concern is that these app genres might seem more popular than they really are. Moreover, these niches seem to be dominated by a few giants who are hard to compete against.

The game genre seems pretty popular, but previously we found out this part of the market seems a bit saturated.

The books and reference genre looks fairly popular as well, with an average number of installs of 8,767,811. It's interesting to explore this in more depth, since we recommended and found this genre has some potential to work well on the App Store, and our aim is to recommend an app genre that shows potential for being profitable on both the App Store and Google Play.

Let's take a look at some of the apps from this genre and their number of installs:

In [23]:
for app in google_final:
    if app[1] == 'BOOKS_AND_REFERENCE':
        print(app[0], ':', app[5])
E-Book Read - Read Book for free : 50,000+
Download free book with green book : 100,000+
Wikipedia : 10,000,000+
Cool Reader : 10,000,000+
Free Panda Radio Music : 100,000+
Book store : 1,000,000+
FBReader: Favorite Book Reader : 10,000,000+
English Grammar Complete Handbook : 500,000+
Free Books - Spirit Fanfiction and Stories : 1,000,000+
Google Play Books : 1,000,000,000+
AlReader -any text book reader : 5,000,000+
Offline English Dictionary : 100,000+
Offline: English to Tagalog Dictionary : 500,000+
FamilySearch Tree : 1,000,000+
Cloud of Books : 1,000,000+
Recipes of Prophetic Medicine for free : 500,000+
ReadEra – free ebook reader : 1,000,000+
Anonymous caller detection : 10,000+
Ebook Reader : 5,000,000+
Litnet - E-books : 100,000+
Read books online : 5,000,000+
English to Urdu Dictionary : 500,000+
eBoox: book reader fb2 epub zip : 1,000,000+
English Persian Dictionary : 500,000+
Flybook : 500,000+
All Maths Formulas : 1,000,000+
Ancestry : 5,000,000+
HTC Help : 10,000,000+
English translation from Bengali : 100,000+
Pdf Book Download - Read Pdf Book : 100,000+
Free Book Reader : 100,000+
eBoox new: Reader for fb2 epub zip books : 50,000+
Only 30 days in English, the guideline is guaranteed : 500,000+
Moon+ Reader : 10,000,000+
SH-02J Owner's Manual (Android 8.0) : 50,000+
English-Myanmar Dictionary : 1,000,000+
Golden Dictionary (EN-AR) : 1,000,000+
All Language Translator Free : 1,000,000+
Azpen eReader : 500,000+
URBANO V 02 instruction manual : 100,000+
Bible : 100,000,000+
C Programs and Reference : 50,000+
C Offline Tutorial : 1,000+
C Programs Handbook : 50,000+
Amazon Kindle : 100,000,000+
Aab e Hayat Full Novel : 100,000+
Aldiko Book Reader : 10,000,000+
Google I/O 2018 : 500,000+
R Language Reference Guide : 10,000+
Learn R Programming Full : 5,000+
R Programing Offline Tutorial : 1,000+
Guide for R Programming : 5+
Learn R Programming : 10+
R Quick Reference Big Data : 1,000+
V Made : 100,000+
Wattpad 📖 Free Books : 100,000,000+
Dictionary - WordWeb : 5,000,000+
Guide (for X-MEN) : 100,000+
AC Air condition Troubleshoot,Repair,Maintenance : 5,000+
AE Bulletins : 1,000+
Ae Allah na Dai (Rasa) : 10,000+
50000 Free eBooks & Free AudioBooks : 5,000,000+
Ag PhD Field Guide : 10,000+
Ag PhD Deficiencies : 10,000+
Ag PhD Planting Population Calculator : 1,000+
Ag PhD Soybean Diseases : 1,000+
Fertilizer Removal By Crop : 50,000+
A-J Media Vault : 50+
Al-Quran (Free) : 10,000,000+
Al Quran (Tafsir & by Word) : 500,000+
Al Quran Indonesia : 10,000,000+
Al'Quran Bahasa Indonesia : 10,000,000+
Al Quran Al karim : 1,000,000+
Al-Muhaffiz : 50,000+
Al Quran : EAlim - Translations & MP3 Offline : 5,000,000+
Al-Quran 30 Juz free copies : 500,000+
Koran Read &MP3 30 Juz Offline : 1,000,000+
Hafizi Quran 15 lines per page : 1,000,000+
Quran for Android : 10,000,000+
Surah Al-Waqiah : 100,000+
Hisnul Al Muslim - Hisn Invocations & Adhkaar : 100,000+
Satellite AR : 1,000,000+
Audiobooks from Audible : 100,000,000+
Kinot & Eichah for Tisha B'Av : 10,000+
AW Tozer Devotionals - Daily : 5,000+
Tozer Devotional -Series 1 : 1,000+
The Pursuit of God : 1,000+
AY Sing : 5,000+
Ay Hasnain k Nana Milad Naat : 10,000+
Ay Mohabbat Teri Khatir Novel : 10,000+
Arizona Statutes, ARS (AZ Law) : 1,000+
Oxford A-Z of English Usage : 1,000,000+
BD Fishpedia : 1,000+
BD All Sim Offer : 10,000+
Youboox - Livres, BD et magazines : 500,000+
B&H Kids AR : 10,000+
B y H Niños ES : 5,000+
Dictionary.com: Find Definitions for English Words : 10,000,000+
English Dictionary - Offline : 10,000,000+
Bible KJV : 5,000,000+
Borneo Bible, BM Bible : 10,000+
MOD Black for BM : 100+
BM Box : 1,000+
Anime Mod for BM : 100+
NOOK: Read eBooks & Magazines : 10,000,000+
NOOK Audiobooks : 500,000+
NOOK App for NOOK Devices : 500,000+
Browsery by Barnes & Noble : 5,000+
bp e-store : 1,000+
Brilliant Quotes: Life, Love, Family & Motivation : 1,000,000+
BR Ambedkar Biography & Quotes : 10,000+
BU Alsace : 100+
Catholic La Bu Zo Kam : 500+
Khrifa Hla Bu (Solfa) : 10+
Kristian Hla Bu : 10,000+
SA HLA BU : 1,000+
Learn SAP BW : 500+
Learn SAP BW on HANA : 500+
CA Laws 2018 (California Laws and Codes) : 5,000+
Bootable Methods(USB-CD-DVD) : 10,000+
cloudLibrary : 100,000+
SDA Collegiate Quarterly : 500+
Sabbath School : 100,000+
Cypress College Library : 100+
Stats Royale for Clash Royale : 1,000,000+
GATE 21 years CS Papers(2011-2018 Solved) : 50+
Learn CT Scan Of Head : 5,000+
Easy Cv maker 2018 : 10,000+
How to Write CV : 100,000+
CW Nuclear : 1,000+
CY Spray nozzle : 10+
BibleRead En Cy Zh Yue : 5+
CZ-Help : 5+
Modlitební knížka CZ : 500+
Guide for DB Xenoverse : 10,000+
Guide for DB Xenoverse 2 : 10,000+
Guide for IMS DB : 10+
DC HSEMA : 5,000+
DC Public Library : 1,000+
Painting Lulu DC Super Friends : 1,000+
Dictionary : 10,000,000+
Fix Error Google Playstore : 1,000+
D. H. Lawrence Poems FREE : 1,000+
Bilingual Dictionary Audio App : 5,000+
DM Screen : 10,000+
wikiHow: how to do anything : 1,000,000+
Dr. Doug's Tips : 1,000+
Bible du Semeur-BDS (French) : 50,000+
La citadelle du musulman : 50,000+
DV 2019 Entry Guide : 10,000+
DV 2019 - EDV Photo & Form : 50,000+
DV 2018 Winners Guide : 1,000+
EB Annual Meetings : 1,000+
EC - AP & Telangana : 5,000+
TN Patta Citta & EC : 10,000+
AP Stamps and Registration : 10,000+
CompactiMa EC pH Calibration : 100+
EGW Writings 2 : 100,000+
EGW Writings : 1,000,000+
Bible with EGW Comments : 100,000+
My Little Pony AR Guide : 1,000,000+
SDA Sabbath School Quarterly : 500,000+
Duaa Ek Ibaadat : 5,000+
Spanish English Translator : 10,000,000+
Dictionary - Merriam-Webster : 10,000,000+
JW Library : 10,000,000+
Oxford Dictionary of English : Free : 10,000,000+
English Hindi Dictionary : 10,000,000+
English to Hindi Dictionary : 5,000,000+
EP Research Service : 1,000+
Hymnes et Louanges : 100,000+
EU Charter : 1,000+
EU Data Protection : 1,000+
EU IP Codes : 100+
EW PDF : 5+
BakaReader EX : 100,000+
EZ Quran : 50,000+
FA Part 1 & 2 Past Papers Solved Free – Offline : 5,000+
La Fe de Jesus : 1,000+
La Fe de Jesús : 500+
Le Fe de Jesus : 500+
Florida - Pocket Brainbook : 1,000+
Florida Statutes (FL Code) : 1,000+
English To Shona Dictionary : 10,000+
Greek Bible FP (Audio) : 1,000+
Golden Dictionary (FR-AR) : 500,000+
Fanfic-FR : 5,000+
Bulgarian French Dictionary Fr : 10,000+
Chemin (fr) : 1,000+
The SCP Foundation DB fr nn5n : 1,000+

The book and reference genre includes a variety of apps: However, it looks like there are only a few very popular apps such as google play books, bible, amazon kindle, Wattpad 📖 Free Books, Audiobooks from Audible - so this market still shows potential.

We also notice there are quite a few apps built around the book Quran, which suggests that building an app around a popular book can be profitable. It seems that taking a popular book (perhaps a more recent book) and turning it into an app could be profitable for both the Google Play and the App Store markets.

Conclusions

In this project, we analyzed data about the App Store and Google Play mobile apps with the goal of recommending an app profile that can be profitable for both markets.

We concluded that taking a popular book (perhaps a more recent book) and turning it into an app could be profitable for both the Google Play and the App Store markets. The markets are already full of libraries, so we need to add some special features besides the raw version of the book. This might include daily quotes from the book, an audio version of the book, quizzes on the book, a forum where people can discuss the book etc.