As a new and mysterious, algorithm-driven field, there are many questions about how app store algorithms work and how to optimize your app listing to gain more visibility and drive more downloads. Today’s article provides answers to some of the most frequently asked ASO questions based on Quora threads, Google searches and conversations with our clients.

  1. What is App Store Optimization?

In a short, ASO is the combination of SEO (search engine optimization) and CRO (conversion rate optimization) for the world of apps, focusing on optimizing your app’s listing for better results.

ASO is like SEO in that the goal is to be found for as many relevant keywords and places in the app store as possible. For visibility optimization-work, the number of store impressions and product pageviews are important metrics of success.

ASO is like CRO in that the goal is to convince as many visitors to download your app as possible. For conversion rate optimization-work, pageview-to-install conversion rate is an important metric of success.

App store optimization begins by creating your app listing (title, description, screenshots, etc.) in either the App Store and continues by tweaking each of your app listing’s elements in order to maximize your visibility and ability to convert visitors into users. ASO is most commonly thought of as finding and using the right keywords and text/visual listing elements, but it can also encompass push campaigns, review flow optimization and getting an app featured, all of which positively influence views and installs.

  1. How does the App Store algorithm work?

First – the category or top chart ranking algorithm (free, paid and grossing) is much simpler than the keyword ranking algorithm. App category ranks improve with more downloads (free or paid) or more revenue from purchases (grossing). While the exact calculation in terms of installs or purchases volume to rank is unknown and varies between categories (e.g. photos and video vs weather), but it is logarithmic (i.e. moving from rank 1000 to 500 is much easier than from moving from 10 to 5) and the most important factors are installs or purchases. Apps will first achieve a rank in their category or sub-category (e.g. #1500 entertainment apps), followed by their country (e.g. #1500 US overall).

The initial factor of the keyword ranking algorithm is whether an app is relevant for that keyword or not. Without being relevant, you app is even eligible to show up (i.e. Facebook is the most popular app but only shows for a certain set of relevant keywords). Relevancy is determined by several factors including those in question #3 below.

For all apps that are relevant for a keyword, each is assigned a keyword rank score that changes with each user interaction (e.g. pageview, install, purchase). An app’s keyword rank score is updated with each interaction and either goes up with positive engagement (e.g. a click, install or review) or goes down with each negative engagement (e.g. an impression but no click, pageview but no install or uninstall before the app is ever used). Apps compete with one another to rank for keywords and when one app’s rank score for a keyword becomes higher than the score of the app above it, it will move up one spot. Engagements are sourced back to each keyword that the user came from, meaning that scores are different from each keyword. That said, engagements for an app overall will improve its ranking for all relevant keywords to some degree, meaning that if Facebook were to become eligible for a new keyword, it would likely start at a very high ranking.

The keyword ranking algorithm is also logarithmic and most installs come from the top 10 ranked apps for a keyword.

  1. How do I rank for keywords?

There are 4 places in an app’s listing that will determine whether it is eligible to rank for keywords:

  • App name
  • App keywords space
  • Developer name
  • App in app purchases (exact match only)

Apple has also been evolving its algorithm to rank apps for keywords not necessarily found in an app’s listing, such as:

  • Partial keyword matches (e.g. ranking “Spotify music app” for “music player app”)
  • Competitor names (e.g. ranking Spotify for Pandora)
  • Common category or other contextual keywords (e.g. ranking Spotify for music-related searches)

Additionally, if a keyword is removed from your app listing (e.g. keywords space), you typically will become immediately ineligible to rank for that keyword.

  1. How can I estimate the volume for each keyword?

There are three main ways to estimate what the search volume of a keyword is. Here are a few of the most common methods:

  • ASO tools (e.g. Mobile Action, SensorTower, Appcodes, TUNE) – these will provide you with a search volume score, which indicates the popularity of a keyword; TUNE will actually provide a real estimate of the number of searches per month. These tools compile data from several sources including their proprietary databases, the google keyword planner tool, store autofill results and trending keywords.
  • App Store Autofill Results – by typing a keyword into the search box you can see the most popular keywords that include that word, such as “free (games, music download, music”). For keywords that are popular enough in the app store, related keywords will also show at the top of a search done from an iPhone or iPad.
  • Google Keyword Planner Tool – this handy, years-old tool provides data on what people are searching on, which while not the same as app store searches, provides generally applicable search trends.
  • Google Trends – this tool allows you to see the popularity of a Google search trend by country or state. While keywords must have significant volume to show up in Google Trends, Trends can help visualize the popularity of a search trend over time better than the keyword planner tool can, even providing data by the hour.
  1. What kinds of ASO tools are there?

There are myriad tools available for researching and managing ASO strategies, most of which encompass a common set of features, such as showing an app’s listing, category rankings, keyword rankings, download estimates, and keyword research like search or difficulty scores. The most common tools include App Annie, Sensor Tower, TUNE (formerly MobileDevHQ), Mobile Action and Searchman.

From our experience, we’ve found the most accurate ranking and keyword results from Mobile Action. App Annie is one of the most well-funded tools with the biggest dataset and the best keyword search preview UI, however, it does not provide much in the way of. TUNE and Searchman both have many unique and useful features, like capturing significant, store-wide changes in rankings (TUNE), or optimizing keyword density in an app’s listing (Searchman), yet both often struggle with data accuracy.

That’s all for today! Thanks for following along – happy optimizing!