15 October 2019

An Introduction to App Store Optimisation (ASO)

Subscribe to our informative Newsletter

Learn about new product features, the latest in technology, solutions, and updates as well as company news.

Andrzej Schmidt

The Google Play marketplace holds 2.5 million apps, and Apple App Store around 2 million. Considering the competition, we’re often asked: “How can I make sure my app gets noticed?”

What you need is ASO. To put it briefly, App Store Optimisation is the process of improving the visibility of your app on the marketplace by making it rank as close to the top in search results as possible. Fine-tuning your listing and getting better exposure gets you those all-important installs.


Let’s talk about your text first

One of the biggest aspects of improving your app store search rankings is the right choice of keywords. This process could be a topic for another post, but the key thing here is to try to find and use words that are relevant to your app, with high traffic and little competition. Usually, long-tail keywords are more effective. To give you an example, it is easier to rank for “mtb coaching” than for “coaching”.
If selecting the right keywords isn’t challenging enough, try to fit them in the tiny amount of space provided on the App Store. The fields that affect your ranking are:

On Google Play:

  • Title (50 characters)
  • Short description (80 characters)
  • Long description (4000 characters)
  • Bundle ID

On App Store:

  • Keywords (100 characters)
  • Title (30 characters)
  • Subtitle (30 characters)
  • App ID

For the App Store it is crucial that you do not repeat the keywords that you have already used in the fields that have the strongest weight in search rankings algorithms. If possible, add your best keyword to the title, but don’t add them again to Keywords field. You have very limited space, so use it wisely and try to add as many different keywords as possible. A neat hack to increase the cap is to localise your app. This way in some cases you can increase the limit up to 500 characters, thus getting a lot more app store search traffic!
It’s important to note another key difference between Google Play and the App Store. Like on Google, you are permitted 4000 characters for your app description. However, unlike Google, this has no influence on your rating. To the contrary, the description on Android store is one of the most important parts in your listing as you do not have a dedicated field for keywords. What also matters is that you repeat all your keywords!

Now that you know what to use and where, don’t forget to review your app performance and don’t be afraid to make changes. However, keep in mind that Apple will reindex everything in around a week while changes on Google can take months…
Visual content and conversion rates
A good ranking will ensure users can find your app, the next step is to make sure it gets installed. We have another handy abbreviation for that – CRO (Conversion Rate Optimization).

Visual assets have a crucial impact on your conversion rate, they take a big proportion of your app listing in the stores and if done right will set you apart and get you those all-important installs. Making a video may be time-consuming but it can increase install rates by more than 23%. The app icon itself can increase your downloads by up to 560%!
If you remember browsing app stores a few years ago, you would usually see a few plain screenshots of the app. While some companies find this sufficient (see Facebook for example) it’s worthwhile spending time designing eye-catching images that contain your app screenshots with added attention grabbing text further explaining the benefits of using the app. Strava does a great job at this, additionally taking you on a journey of all main features. Others like Airbnb use available space to compose a bigger image to get your attention.

Think about your brand, make sure that the background colour, font and screenshots that you’re showcasing are high quality, consistent with your brand and relevant. Keep in mind that if you localise your text, you can (or rather should) do that for screenshots and videos too. Unfortunately, the same visual approach won’t work for all apps! You will need a bit of patience in order to test out and experiment with different options to see what works best for your app and what appeals to your target.


Your App Rating

According to some online stats, improving your app store rating from two to three stars can boost your app store conversions by 280%, while shifting from two to four stars will increase conversions by 540%. If you get an unfavourable review don’t get upset, remember that responding to your negative reviews can turn negative feedback into a positive one.

Luckily, Apple allows you to reset ranking when uploading a new version which benefits apps with negative reviews. Saying that, by no means should you just wait for negative feedback. You should actively prompt users to leave you a good rating. A good strategy here is to ask once in a while whether your users are enjoying using the app. If the answer is positive you can prompt them to leave a rating, if not you can give them a chance to give you feedback and act on it before others complain too.


ASO can sometimes be described as SEO for apps, however, as you can see, this would be a big oversimplification. In recent years Google Play and the App Store have evolved, and have grown to have many similarities, yet key differences in ASO remain.


  • Do not repeat your keywords on iOS, try to use all available ranking fields. Avoid plurals, write numbers as digits and use localisation!
  • Do repeat keywords on Android listings and remember your reviews also matter.
  • It’s better to rank high for a less popular keyword than to rank #30 for a highly-searched one.
  • Take time to create visual assets and sell your brand and app features.
  • Don’t wait for reviews, prompt users to rate you when they are happy with your app. And don’t forget that keywords in reviews are important in Google Play.
  • If you really have to, you can reset your reviews on Apple and start with a clean slate.
  • Check tools like Sensor Tower, App Radar, ASOdesk, TheTool to monitor and improve your ranking.