Our aim in this project is to find mobile app profiles that are profitable for the App Store and Google Play markets. We're working as data analysts for a company that builds Android and iOS mobile apps, and our job is to enable our team of developers to make data-driven decisions with respect to the kind of apps they build.
At our company, we only build apps that are free to download and install, and our main source of revenue consists of in-app ads. This means that our revenue for any given app is mostly influenced by the number of users that use our app. Our goal for this project is to analyze data to help our developers unAs of September 2018, there were approximately 2 million iOS apps available on the App Store, and 2.1 million Android apps on Google Play.
As of September 2018, there were approximately 2 million iOS apps available on the App Store, and 2.1 million Android apps on Google Play.
Collecting data for over four million apps requires a significant amount of time and money, so we'll try to analyze a sample of data instead. To avoid spending resources with collecting new data ourselves, we should first try to see whether we can find any relevant existing data at no cost. Luckily, these are two data sets that seem suitable for our purpose:
Let's start by opening the two data sets and then continue with exploring the data.
opened_file = open('AppleStore.csv')
from csv import reader
read_file = reader(opened_file)
ios = list(read_file)
ios_header = ios[0]
ios = ios[1:]
opened_file = open('googleplaystore.csv')
from csv import reader
read_file = reader(opened_file)
android = list(read_file)
android_header = android[0]
android = android[1:]
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 after each row
if rows_and_columns:
print('Number of rows:', len(dataset))
print('Number of columns:', len(dataset[0]))
print(android_header)
print('\n')
explore_data(android, 0, 3, True)
print (ios_header)
print('\n')
explore_data(ios, 0, 3, True)
print(android[10472]) # incorrect row
print('\n')
print(android_header) # header
print('\n')
print(android[0]) # correct row
print(len(android))
del android[10472] #do not run all cells henceforth.
#always run each new cell independently so as to avoid
#deleting the new row 10472
print(len(android))
for application in android:
name = application[0]
if name == 'Instagram':
print(application)
duplicate_apps = []
unique_apps = []
for app in android:
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))
print('\n')
print('Examples of duplicate apps:', duplicate_apps[:15])
We are going to have to remove duplicate apps so as not two count app more than once. This can be done randomly, but we can find a better way to do it.
If we observe the duplicate Instagram apps, we would notice that they have different number of reviews. We could pick the duplicate apps with the highest number of reviews. High number of reviews simply tells us that that data is more reliable than others with lesser reviews.
In order to do that, we will:
Let's start by building the dictionary.
reviews_max = {}
for app in android:
name = app[0]
n_reviews = float(app[3])
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
In a previous code cell, we found that there are 1,181 cases where an app occurs more than once, so the length of our dictionary (of unique apps) should be equal to the difference between the length of our data set and 1,181.
print('Expected length:', len(android) - 1181)
print('Actual length:', len(reviews_max))
We're now going to use the reviews_max dictionary to remove the duplicates. For the duplicate cases, we'll only keep the entries with the highest number of reviews. In the code cell below:
android_clean = []
already_added = []
for app in android:
name = app[0]
n_reviews = float(app[3])
if (reviews_max[name] == n_reviews) and (name not in already_added):
android_clean.append(app)
already_added.append(name)
explore_data(android_clean, 0, 3, True)
print(ios[813][1])
print(ios[6731][1])
print(android_clean[4412][0])
print(android_clean[7940][0])
def is_english(string):
for character in string:
if ord(character) > 127:
return False
return True
print(is_english('Instagram'))
print(is_english('爱奇艺PPS -《欢乐颂2》电视剧热播'))
print(is_english('Docs To Go™ Free Office Suite'))
print(is_english('Instachat 😜'))
def is_english(string):
non_ascii = 0
for character in string:
if ord(character) > 127:
non_ascii += 1
if non_ascii > 3:
return False
return True
print(is_english('爱奇艺PPS -《欢乐颂2》电视剧热播'))
print(is_english('Docs To Go™ Free Office Suite'))
print(is_english('Instachat 😜'))
android_english = []
ios_english = []
for app in android_clean:
name = app[0]
if is_english(name):
android_english.append(app)
for app in ios:
name = app[1]
if is_english(name):
ios_english.append(app)
explore_data(android_english, 0, 3, True)
print('\n')
explore_data(ios_english, 0, 3, True)
android_final = []
ios_final = []
for app in android_english:
price = app[7]
if price == '0':
android_final.append(app)
for app in ios_english:
price = app[4]
if price == '0.0':
ios_final.append(app)
print(len(android_final))
print(len(ios_final))
We're left with 8864 Android apps and 3222 iOS apps, which should be enough for our analysis
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:
Build a minimal Android version of the app, and add it to Google Play.
If the app has a good response from users, we then develop it further.
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. For instance, a profile that might work well for both markets might be a productivity app that makes use of gamification.
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.
We'll build two functions we can use to analyze the frequency tables:
One function to generate frequency tables that show percentages Another function that we can use to display the percentages in a descending order
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)
for entry in table_sorted:
print(entry[1], ':', entry[0])
We start by examining the frequency table for the prime_genre column of the App Store data set.
display_table(ios_final, -5)
We can see that among the free English apps, more than a half (58.16%) are games. Entertainment apps are close to 8%, followed by photo and video apps, which are close to 5%. Only 3.66% of the apps are designed for education, followed by social networking apps which amount for 3.29% of the apps in our data set.
The general impression is that App Store (at least the part containing free English apps) is dominated by apps that are designed for fun (games, entertainment, photo and video, social networking, sports, music, 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 greatest 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).
display_table(android_final, 1) # Category
The landscape seems significantly different on Google Play: there are not that many apps designed for fun, and it seems that a good number of apps are designed for practical purposes (family, tools, business, lifestyle, productivity, etc.). However, if we investigate this further, we can see that the family category (which accounts for almost 19% of the apps) means mostly games for kids.
Even so, practical apps seem to have a better representation on Google Play compared to App Store. This picture is also confirmed by the frequency table we see for the Genres column:
display_table(android_final, -4)
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 granular (it has more categories). 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.
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:
genres_ios = freq_table(ios_final, -5)
for genre in genres_ios:
total = 0
len_genre = 0
for app in ios_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)
On average, navigation apps have the highest number of user reviews, but this figure is heavily influenced by Waze and Google Maps, which have close to half a million user reviews together:
for app in ios_final:
if app[-5] == 'Navigation':
print(app[1], ':', app[5]) # print name and number of ratings
The same pattern applies to social networking apps, where the average number is heavily influenced by a few giants like Facebook, Pinterest, Skype, etc. Same applies to music apps, where a few big players like Pandora, Spotify, and Shazam heavily influence the average number.
Our aim is to find popular genres, but navigation, social networking or music apps might seem more popular than they really are. The average number of ratings seem to be skewed by very few apps which have hundreds of thousands of user ratings, while the other apps may struggle to get past the 10,000 threshold. We could get a better picture by removing these extremely popular apps for each genre and then rework the averages, but we'll leave this level of detail for later.
Reference apps have 74,942 user ratings on average, but it's actually the Bible and Dictionary.com which skew up the average rating:
for app in ios_final:
if app[-5] == 'Reference':
print(app[1], ':', app[5])
However, this niche seems to show some potential. 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. This might include daily quotes from the book, an audio version of the book, quizzes about the book, etc. 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.
Other genres that seem popular include weather, book, food and drink, or finance. The book genre seem to overlap a bit with the app idea we described above, but the other genres don't seem too interesting to us:
Weather apps — people generally don't spend too much time in-app, and the chances of making profit from in-app adds are low. Also, getting reliable live weather data may require us to connect our apps to non-free APIs.
Food and drink — examples here include Starbucks, Dunkin' Donuts, McDonald's, etc. So making a popular food and drink app requires actual cooking and a delivery service, which is outside the scope of our company.
Finance apps — these apps involve banking, paying bills, money transfer, etc. Building a finance app requires domain knowledge, and we don't want to hire a finance expert just to build an app.
Now let's analyze the Google Play market a bit.
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.):
display_table(android_final, 5) # columns showing number of installations
One problem with this data is that is not precise. For instance, we don't know whether an app with 100,000+ installs has 100,000 installs, 200,000, or 350,000. However, we don't need very precise data for our purposes — we only want to get an idea which app genres attract the most users, and we don't need perfect precision with respect to the number of users.
We're going to leave the numbers as they are, which means that we'll consider that an app with 100,000+ installs has 100,000 installs, and an app with 1,000,000+ installs has 1,000,000 installs, and so on.
To perform computations, however, we'll need to convert each install number to float — this means that we need to remove the commas and the plus characters, otherwise the conversion will fail and raise an error. We'll do this directly in the loop below, where we also compute the average number of installs for each genre (category).
categories_android = freq_table(android_final, 1)
for category in categories_android:
total = 0
len_category = 0
for app in android_final:
category_app = app[1]
if category_app == category:
n_installs = app[5]
n_installs = n_installs.replace(',', '')
n_installs = n_installs.replace('+', '')
total += float(n_installs)
len_category += 1
avg_n_installs = total / len_category
print(category, ':', avg_n_installs)
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:
for app in android_final:
if app[1] == 'COMMUNICATION' and (app[5] == '1,000,000,000+'
or app[5] == '500,000,000+'
or app[5] == '100,000,000+'):
print(app[0], ':', app[5])
If we removed all the communication apps that have over 100 million installs, the average would be reduced roughly ten times:
under_100_m = []
for app in android_final:
n_installs = app[5]
n_installs = n_installs.replace(',', '')
n_installs = n_installs.replace('+', '')
if (app[1] == 'COMMUNICATION') and (float(n_installs) < 100000000):
under_100_m.append(float(n_installs))
sum(under_100_m) / len(under_100_m)
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, so we'd like to come up with a different app recommendation if possible.
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 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:
for app in android_final:
if app[1] == 'BOOKS_AND_REFERENCE':
print(app[0], ':', app[5])
The book and reference genre includes a variety of apps: software for processing and reading ebooks, various collections of libraries, dictionaries, tutorials on programming or languages, etc. It seems there's still a small number of extremely popular apps that skew the average:
for app in android_final:
if app[1] == 'BOOKS_AND_REFERENCE' and (app[5] == '1,000,000,000+'
or app[5] == '500,000,000+'
or app[5] == '100,000,000+'):
print(app[0], ':', app[5])
However, it looks like there are only a few very popular apps, so this market still shows potential. Let's try to get some app ideas based on the kind of apps that are somewhere in the middle in terms of popularity (between 1,000,000 and 100,000,000 downloads):
for app in android_final:
if app[1] == 'BOOKS_AND_REFERENCE' and (app[5] == '1,000,000+'
or app[5] == '5,000,000+'
or app[5] == '10,000,000+'
or app[5] == '50,000,000+'):
print(app[0], ':', app[5])
This niche seems to be dominated by software for processing and reading ebooks, as well as various collections of libraries and dictionaries, so it's probably not a good idea to build similar apps since there'll be some significant competition.
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.
However, it looks like the market is 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.
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.