According to Google’s research “Mobile App Marketing Insights: How Consumers Really Find and Use Your App” (2015), apps are often discovered outside the app store. The main sources of awareness of smartphone apps are the following:

52% friends, family, and colleagues
40% browse the app store
27% search engines
24% company website
22% TV

Since 40% of users discover apps browsing the app store, it is important to gain visibility in the app stores. The perfect way to achieve that is with ASO (App Store Optimization). ASO consists basically of improving the visibility of your app in an app store by getting higher ranks in the app store’s search results.

Like SEO, it is a long-term marketing strategy. It is not something that you can do once and forget about it because, among other things, you would need to monitor your keyword rankings regularly.

When done right, it is also a very cost-effective way to get more downloads. When you do paid advertising, you stop getting downloads the moment you stop your campaigns. This is not the case with ASO.

ASO key elements

  • Keywords
  • Icon
  • Screenshots/video
  • App description
  • Category
  • Ratings/reviews
  • Updates


Keyword optimization differences between how keywords are detected in the Apple App Store and in the Google Play Store.

Apple App Store

The algorithm employed by the Apple App Store uses primarily keywords coming from the app title (app name) to rank apps for specific search queries, and also the iTunes Connect Keyword Field.

The app name has a limit of 50 characters and, according to the App Store Review Guidelines, should not include terms or descriptions that are not the name of the app. App store keywords place in the app title have more weight that the ones in the keyword field. So, use your most relevant keywords in the title (app name).

iTunes Connect Keyword Field has a limit of 100 characters. If you want to use long tail keywords, you need to separate every term using a comma. The algorithm combines automatically all the keywords together. For example, if you want to rank for the keyword photo editor, don’t enter the term like this “photo editor” but like this “photo, editor”.

In the Apple App Store, to update your app keywords, you have to submit a new app update and go through the review process. The downside of doing this is that your app’s current ratings will reset to zero. The average rating that displays in search results will be reset. The existing ratings will still be available in the overall rating average.

Google Play Store

The app title is only 30 characters, which means that you need to be more selective when deciding what keywords to use.

The keywords for your Google Play Android app are pulled from the description of your app, which has a 4,000 character limit. It’s recommended that you include your keywords at least 4 to 5 times in the description.

Process for keyword optimization in any app store

  • Research initial keywords and select the best ones according to their relevance, difficulty, and search volume.
  • Track rankings. You should keep a set of keywords for three to four weeks to see if they are working.
  • Review your rankings at least once a week
  • If your targeted keywords are not ranking in the top 10 positions, do your research again to find replacement keywords
  • Implement keyword changes
  • Track rankings again and repeat the steps until all your keywords are ranking in the top 10.

There are three characteristics that are important when you select your keywords:

  • Download relevance
  • Difficulty (competition)
  • Traffic (search volume)

The most important characteristic you are looking for in a keyword is relevance. You need to find all the keywords people may use to download your app. When ranking keywords, the Apple App Store algorithm takes into consideration the conversion rate. If your keywords are relevant, they’ll have a higher conversion rate and they’ll rank higher.

Competition (keyword difficulty). Your goal is to get your keywords to rank in the top 10 results since the majority of people don’t bother to scroll down farther than that. Different ASO platforms measure the difficulty metric in different ways.

Part of the ASO process is to keep monitoring your keyword rankings and keep only the keywords that rank higher, bring traffic, and of course downloads. Also, keep in mind that keyword rankings are not static and you should monitor them at least once a week.

Another characteristic your keywords should have is search volume. Like with keyword difficulty, most ASO tools provide their own volume estimations.

How to find the initial keywords and the new ones

Create a spreadsheet to keep track of all your keywords, write down your keyword ideas, the keywords you are using, the ones you want to use next, etc.

Start looking for new keywords when you are not ranking in the top 10 for all your targeted keywords, and/or your previous keyword changes did not increase app downloads.

Some ways to find keywords

  • Spy your competitors. What keywords are they using in their description, app title, users’ reviews. Use some ASO tool to find out the keywords they are ranking for.
  • Use a thesaurus to find synonyms.
  • Check your own app reviews if you have them. If you don’t have reviews yet, check your competitors’ reviews.
  • Use a keyword research tool like Google Keyword Planner, Wordstream.
  • Web sites about your app subject.


Your app icon is like the face of your app, it’s the first thing people is going to see. When designing your icon, consider two broad design categories: branded and descriptive.

Branded. For this type of icon, use your company logo and colors.

Descriptive. For this kind of icon, focus on one key feature of your app. If it’s a functional app, highlight the most important feature. If it’s a game you can focus on one of the characters for example.

Icon best practices

  • App icons should be as simple as possible.
  • Follow app store guidelines
  • The icon design must be consistent with your app design (similar coloring, branding). People should be able to clearly identify your app through its icon once they have downloaded and installed the app on their phones.
  • Don’t use words since it’s difficult to see them.
  • Be sure the icon is understandable at its smallest size.

Icon design guidelines Android
Icon design guidelines Apple
iOS icon gallery for inspiration
How to design better app icons


The main purpose of the screenshots is to show how your app looks like and what the app does. It is also the first impression a customer gets about your app, so make it count. The quality of your app is judged based on the quality of the screenshots. Only the app reviews have a stronger influence on that perception. App screenshots have two simple jobs: grab the attention of potential customers and convince them to download the app.

Screenshot best practices

  • Use all available screenshot slots
  • Use the first screenshot to show the best app feature
  • Each screenshot should communicate one benefit of your app
  • Use additional text to highlight the benefit displayed on each screenshot
  • Don’t use generic screens like menus
  • Pay attention to screen orientation, examine the screenshot on devices, and use the right dimensions
  • Localize your screenshots

Video best practices

  • Videos for the App Store and Google Play Store have very different formats and constraints. See here Videos App Store vs Play Store.
  • Grab the user attention in the first 5 seconds
  • Establish a good pace
  • Change screens often to keep people interested
  • Use professional voice talent and interesting music
  • Follow the app store guidelines
  • Assume people have the sound turned off
  • Use an attention grabbing first frame or poster image
  • Make sure your video looks good on small and big screens
  • Highlight you best benefits first
  • See what other successful apps are doing, and take notes about the things you like and don’t like
  • Have a call to action at the end of the video

Test the screenshots and video to see what is working for you, what is driving more downloads and installs.

App previews (video on the iOS App Store)
App screenshot guide
App previews Apple

App description

Why is app description important for ASO? Since 40% of users discover apps browsing the app stores, Google Play Store and Apple App Store have a ranking algorithm implemented to rank search results properly. The keywords the algorithm uses are pulled from different fields (app title, keyword field, description). The ones from the description are especially important in the Play Store.

The description is your last chance to convince people to download your app. In general, the description can be more important for a paid app than for free apps since you have to convince the user to pay before installing the app.

A good description explains clearly what the app is about and shows the most crucial facts above the fold. It should contain a list of the main features and functionality and include support contact and a link to the website.

Another thing to keep in mind when writing the description is keyword density  (the percentage of times a keyword appears on a page compared to the total number of words on the page).

Apple App Store

Use the first three lines above the fold to grab user attention. This is what users can read without having to tap “more”.

The keywords are not taken from the description. In the Apple App Store, apps are ranked based on a number of factors: Matches for your app’s title, keywords (iTunnes Connect Keyword Field) and primary category, the downloads and the number and quality of ratings and reviews.

The description is limited to 4,000 characters.

Google Play Store

Google uses the keywords from the description to rank your app. You can use emojis and rich text formatting.
The description is limited to 4,000 characters.


Categories allow new users to find the app that better suits their needs.In the App Store, you can assign two categories to your app, a primary and a secondary category. The primary category is where your app will be displayed in search results and top charts.

When deciding what category to choose, consider your app main function or subject matter, where users would naturally search for an app like yours, and which categories contain apps similars to the one you have.


Ratings are an integral part of the ranking algorithm for app searches in the App Store and the Play Store. They are crucial to driving rankings, discovery, downloads, and in-app purchases.

In 2013, Apple changed its app store search algorithm to place more importance on ratings and reviews. Apps with average ratings under three stars ranked significantly lower, and apps with ratings of at least four stars ranked higher.

These are some of the factors used by both app stores to calculate search rankings:

  • Rating/review quantity
  • Rating/review quality
  • Download count
  • App usage statistics
  • Uninstalls
  • Growth
  • Keyword density of the app’s landing page

Reviews are important because they qualify your ratings, give you valuable feedback that can help you improve your app since they provide actionable insights, and they also provide a communication channel to your customers.

Usually, reviews occur in response to one of the following experiences:

  • Leave a negative review after a bad experience (65%)
  • Leave a positive review after a good experience (49%)
  • Leave a review to report a bug in the app (43%)
  • Leave a review to suggest a new feature (22%)
  • Leave a review to comment on a version difference after an update of the app (15%)

Some numbers to keep in mind  from a survey done by Apptentive: About 70% of people read at least one review before downloading an app, and 75% identifies reviews as a key driver for downloading an app. However, only 36% of people say they have left a review in the app store.

Main differences between App Store and Play Store

  • There is a difference in the way they handle app ratings.

The App Store presents historic ratings and, more prominently, the average rating for the current version of the app. iOs apps typically suffer from low ratings for a one-week period after launching a new update, but offer publishers more control over boosting their ratings with a well-received update.

Google Play ratings are more historic (the average of all ratings since app’s launch) and harder to change without a significant volume of new reviews.

iOs ratings are significantly more volatile than Android rankings. Meaning, it is possible for a new app to dethrone high.ranking competitors within weeks.

  • Play Store offers app publishers the autonomy to make changes to their app’s description and listing at will.

For iOs developers, any changes to the app’s landing page must be approved by Apple. Any changes to the app’s title, keywords, icon, or screenshots will constitute a new app version, and ratings reset.

  • Google Play Store places less emphasis on the role of ratings and reviews as social proof by showing app downloads as an alternative indicator of popularity.

How to increase ratings and reviews

Always respond to reviews whether they are positive or negative. With positive reviews, a simple thank you may be enough but add your personal touch.

With negative reviews, address any complaints or issues explaining why that specific problem exists and what steps you are taking in order to solve it.

One way to increase your ratings and reviews is using a rating prompt. A rating prompt is a proactive in-app message that asks people to rate your app. Usually, they provide three options to the user: rate the app, remind me later, no thanks.

Prompting is an effective tool to achieving a higher volume of ratings and reviews and achieving a higher concentration of positive reviews and 5-star ratings.

Prompt best practices

  • Identify key moments of engagement (moment of success or completion) within the app to figure out where to place the rating prompt.
  • Instead of asking for a rating as soon as someone installs your app, give them some time to use it and then ask them if they like the app. If they do, ask them to rate it. If they don’t like your app, ask them to give you some feedback.
  • Use a rating prompt once per customer to avoid asking for a rating to someone who has already rated your app.
  • For better results, target your most loyal customers, those that do an extended use of your app.
  • Never solicit a rating/review at the moment of launch, and never interrupt the user activity.
  • Deliver the message when a customer completes a specific task rather than at the beginning or in the middle.


Updates may be a way to show your potential users how much you care about your app, that you are still there and the app is not abandoned.

Updates allow you to fix bugs, add features that users are requesting, and keep your users engage.

When updating your app, take advantage of the “What’s New” section. Use this section to explain the changes you have made, errors that had been fixed. You can also use this section to ask for feedback. Update your description and use the occasion to change visual elements like the screenshots.

How often should you update your app?

Preparing for ASO in iOS 11

Apple is reducing the maximum characters in the app name from 50 to 30 characters. Apple decided to add the new app subtitle field to make up for the loss. This is similar to the short description on Google Play and is limited to 30 characters in iOS 11.

Promotional Text. This is another new field that appears above the app description. It allows app publishers to use a maximum of 170 characters to further communicate the value of their app.

Preview Videos get an upgrade in iOS 11.

  • Display up to 3 videos on your product page
  • Videos can now be localized
  • Videos autoplay without sound on your app’s product page
  • Videos appear before screenshots

Ratings. In iOS 10, whenever an update is published, the average rating of the app is reset. Only the overall average rating will be displayed in iOS 11. You will also be able to determine when you reset the average rating of your app.

Other elements of your app will appear in search results, not just your app’s profile page. This includes: developers, in-app purchases, categories, editorial stories, tips and tricks, collections

Although the Top Charts option will be removed from the iOS 11 menu, the category ranking will still show up on the product page.

Another new addition to the App Store is the ability to promote your in-app purchases on your product page. Each IAP will have its own title, promotional image, and description.

App store optimization the essential ASO resources list
Mobile App Marketing Insights: How Consumers Really Find and Use Your App (2015)
ASO for iOS guide
iOS 11 ASO
App Store Optimization Stack
ASO crash course
ASO app name and keywords
Optimize Play Store app
App Store Review Guidelines
Making the most of your product page on the all-new App Store
Graphic assets, screenshots, & video Google Play Store
Case Study – How CallApp Increased Google Play App Ratings by 80% and Reduced Negative Feedback by 70%
How to Optimize Your Google Play Store Listing for ASO – Ultimate Guide
How to Design Outstanding App Screenshots and Get More Installs

ASO tools
Sensor Tower
App Annie
App Radar
App Tweak
Search app keywords