Why App Store Optimisation?

“App store optimisation (ASO) is the process of improving the visibility of a mobile app (such as an iPhone, iPad, Android, or Windows Phone app) in an app store (such as iTunes or Google Play for Android). App store optimisation is closely related to search engine optimisation. Specifically, app store optimisation includes the process of ranking highly in an app store’s search results and top charts rankings. ASO marketers agree that ranking higher in search results and top charts rankings will drive more downloads for an app.” – Wikipedia

It is generally much easier to do than SEO as the App Store is less mature so it doesn’t take much effort. Plus it’s free and the effects are long lasting. Everyone should do this because of the huge ROI (Might have considerable effect and it does not take much time once you understand it).

In this article we will cover the general ASO Advice, take a look at a few ASO tools on the market and do a run through of an example using my own hobby app – Fav Alert

What are the common features?

ASO tools have a few common features that are useful to an App Developer. Here are the most common features that gives you some insight of how you are doing and what the competitive landscape is.

1. Ranking across Countries and Categories

iOS App stores have rankings separated by countries. You can be the top selling app in the Taiwan store but no one from US have heard of your app. With ASO Tools, you can easily see which countries and what categories are you ranking well for.

This might come in useful if you break into the top charts of a country. You can then place that badge of honor in your app description which provides social proof of your popularity in a country that does not know your app yet and drive more downloads. It also gives you a focus on which country you can direct your marketing effort in so as to push your app to the Top ranks of a certain country.

See also: Mobile games account for top global apps worldwide in Jan 2014

2. Track Downloads/Revenue

iTunes Connect is getting better since it start out but honestly it’s still pretty bad for developers! In a world where data lives forever, the daily downloads tracker only goes back up to one month!

ASO Tools have take it upon themselves to scrape iTunes and store the data forever so that you can see historical trends and never lose that data.

Another thing I like is that some of the ASO tools send you daily reports which saves you the trouble of logging in daily. It’s a good start to a day when you wake up to a email report of $IAPs and also see new reviews that have been posted.

3. Track Competitors

With millions of apps in the App store, you will definitely have a competitor or two. You can keep tabs on your competitors ranking, estimated net worth, App review and blog mentions.

For example, if this was a competitive app – ChatNow Pro, you could see potential keywords from the reviews that people left and maybe what features you should be adding.

You can also use Keyword Spy to see if there are any keywords you should be using. They might be doing well so lets see what people are searching for


Use Reviews to screen for potential keywords on your competitor’s apps

4. Indicator of Difficulty/Traffic for keywords

Most ASO wants to help you improve your app ranking for higher downloads and better organic discovery. So they give you an idea of how difficult and how much traffic there is likely for a keyword. This is the most useful actionable part of ASO tools and it is very useful later when you are selecting keywords to try so we will be focusing most of the article on this.

Stuff that is important to search


App Icon, Screenshot (First), Ratings, Screenshot (The Rest), App Title

There are a couple of things that are also important to search which is obvious once you take a look at how search results are displayed in the iPhone

They are:

  1. App Icon
  2. Screenshot (First)
  3. Ratings
  4. Screenshot (The Rest)
  5. App Title

These affect if a person is likely to click in the app to check it out more. I will highlight these but this article is focused on ASO so I will only elaborate on the App Title.

App Titles

App Titles are sometimes much more important than keywords because the keywords in the title also count and some say are important than the explicit keywords you enter into iTunesConnect. Like keywords, they can only be changed with each update so you should test the Title before using it.

There are 2 tests here. The first is similar to the keywords. Having good keywords helps your app rank higher. The second is the visible part of the title. This varies by the device with the following characters visible.

iPhone: ~ 30 chars visible
iPad: ~53 chars visible
Desktop iTunes: ~ 30 chars visible

Thus a good title should have the first 30 chars optimised for communicating the intent of the app and the rest used for keyword rankings. Titles are limited to 255 characters limit so feel free to go as far as you can. *Do note that in some cases, Apple Review do reject App titles that are too “optimised”

To do this, I usually do my first 30 character testing of Facebook ads so I have a good prediction of which 30 characters makes for the best CTR.

Here is an example of an app that really fully uses a really really long title:


“SofaScore LiveScore – Sports live scores and results, Football – Soccer (Brazil 2014, Premier, Champions) league table, fixtures & video highlights, Tennis (ATP & WTA), Basketball games, Ice Hockey (NHL), Super Rugby score, Union (Six Nations), MLB.”

Good Keywords are Relevant and High Rank

With ASO Tools, the goal is to choose correct keywords so that when some one searches, they see your app. Thus like Web SEO, the best keywords are those that relevant and rank highly (<#10 when you search )

Relevant = People typing in this keyword have a good chance of being interested in your app
Rank Highly = Top 10 in ranking because we know no one scrolls past even the 5th app.

How to use Sensor Tower
Now that you understand the concepts behind ASO, lets cover how to use Sensor Tower to do ASO.

1. Choose country you want to rank for
This is important because all rankings are country specific but the keywords you enter are not! Your keywords apply for all countries until you add internationalisation. Internationalisations allows you too add language/country specific title, description and keyword. This adds a lot more work but can help you change keywords per country. If you have done internationalisation, the steps are the same. Just that you have to repeat it per country.

2. Picking Keywords
For iOS Apps, Keywords only can be changed for each update. This means you need to actually submit an update to your app often else you can’t really test ASO.
While you are submitting an update, you should pick the keywords that are a balance of relevant and highly likely to rank.

Relevance is really hard to tell. Unfortunately there is no way to link search terms to downloads. So you have to use your gut feel for that.

For Likeliness to rank, ASOs provide you with some data points.


Traffic, Difficulty and number of competing apps

Of course for new keywords, your app probably has no rank. but that’s OK. What you want is a prediction of how likely it will rank highly before you actually use the keyword in a App update. This is really useful because even at the shortest, ASO keywords is a 2 week affair where 1 week is spent waiting for approval and another few days for rankings to be affected.

Here the important fields are

  1. Traffic = How many people search for this keyword
  2. iPhone Difficulty = How hard it will be to rank highly in a meaningful number
  3. iPhone Apps = Competing apps that also rank for the chosen keyword. You want to avoid keywords with thousands of apps. Its going to be difficult unless you have the keyword in your title and a lot of people download your app.

I use a spreadsheet with some simple arithmetic to see if a keyword is worth trying.


Spreadsheet to track changes across versions

In the Spreadsheet, I discard bad ROI Keywords (Traffic/Difficulty) and those with competing Apps of more than 1000 since it is unlikely you will ever rank well for them.

I also track results across versions so that I can discard a keyword forever it the ranking is bad. Sometimes the prediction does not reflect actual app store. Like in v2.9, iMessage seem to be a promising keyword but it didn’t even rank.

Maximising your keywords of 100 chars

A couple more tips in terms of choosing keywords and maximising the limited space

  • use all keywords (100 Chars)
  • short keywords have more high traffic
  • Single words rather than phrases
  • Word in title rank highly and do not need to be duplicated
  • Singular rather than duplicate
  • Words in Company name already are ranked
  • Not big company names that are trademark (might get rejected)

Viable Alternatives to Sensor Tower

These are my 2 other alternatives that I tried. They each have their plus and minus so feel free to check them out yourself.

Mobile Dev HQ:

  • Sonar: check if App Store has big changes or its just your app. Know if your changes are effective.
  • Easily track across multiple countries


  • Very competitor driven. Great for seeing how your app is doing vs the competition.

Sometimes different ASO Tools provide different data so it’s good to check them out. I still use SensorTower mainly because the UX seems to be the most thought out.


I hope you have the basic concepts of ASO and have a practical understanding of how to do it. It’s a pretty iterative process but can have great impact if you do it well.

See also: [Updated] Distimo report terms Asia as ‘leading app market in the world’