A/B testing

A/B testing, multivariate- or split testing, is the act of presenting a percentage of your users with small changes to your app and then testing the effectiveness or performance of these changes to the original. For example, you can test different button colors, text or layout, and measure which produces more clicks, purchases, etc.

Affiliate marketing

A practice in which one party rewards another for each user acquired by the affiliate marketing efforts.


Average Revenue Per Daily Active User. An estimate of the amount of revenue generated by users on any given day. As a monetization metric, ARPPU and ARPU are better indicators of trends.
ARPDAU is calculated as Total Revenue for a Given Day / Number of Active Users that Day.


Average Revenue Per User is your average earnings per user. This indicator varies strongly between game genres.
ARPU is calculated as Total Revenue per Month / Total Number of Unique Users per Month.


Average Revenue Per Paying User.
ARPPU is calculated as Total Revenue per Month / Total Number of Unique Paying Users per Month.

Casual Game

This term usually signifies a game which can be played in short sessions, has simple controls, an easy learning curve, yet increasing level of difficulty.

Churn Rate

This is the percentage of users who leave your app during a certain period.


The Click-Through Rate is the ratio of clicks, as apposed to views/impressions, which an ad receives.
CTR is calculated as Clicks / Impressions.


A grouping of users by a specific action or status within a certain time-frame. By comparing the cohorts from different time-frames, gives you, for example, an indication of the effectiveness of a marketing campaign or promotion.

Conversion Rate

The percentage of users who convert from free to paying users.


Cost Per User, is the cost of acquiring a new user.


Cross-platform apps are developed once and can be deployed to multiple operating systems.


Cost Per Acquisition/Conversion is the cost for acquiring a user, or to convert a user to a paying user.


Cost Per Click is the average cost for a user who clicks an ad.
CPC is calculated as Total Advertising cost / Total Clicks.


Cost Per Install
CPI is calculated as Total Advertising Cost / Total Installs.


Cost Per 1000 Impressions or Cost Per Thousand is the cost per thousand views of an ad.
CPM is calculated as Total Advertising Cost / Total Impressions * 1000.


Consumables are in-game items which can be earned as collectibles, unlocked or purchased. Their number gets reduced on use. The app or game may have a mechanism through which these get replenished over time. Examples are health potions or special attacks.


Conversion is the act of getting a user to perform a desired action. Typically it means converting a free user to a paying user.


Click Through Rate is the number of clicks divided by the number of impressions, expressed as a percentage.
CTR is calculated as Total Clicks / Total Impressions * 100.


Daily Active Users is the number of unique users who opened your app at least once on a given day.


DAU/MAU is the ratio between your Daily Active Users and Monthly Active Users of the preceding 30 day period. If this ratio falls, then you are loosing users.


Dolphins are mid-tier spenders, in relation to the high and low spenders in your app.


Effective Cost Per Acquisition is the real cost per acquisition. Keep this figure less than the expected LTV to have a positive return on user acquisition.


This term is used to indicate the frequency with which users open your app. A good measure of engagement is DAU/MAU.


An Event is the term used for actions which a user takes within your app, e.g. making a purchase, a user completes the tutorial, etc.


Free to play, indicating an app which has no initial cost to acquire. Monetization usually happens through IAPs and/or ads.


Indicating an app which has no initial cost to acquire, however, monetization usually happens through unlocking paid premium content.


A funnel is defined as a set of related events inside of your app which lead to a specific action, eg. an in-app purchase. Using funnels in reporting gives you a better understanding of how users interact with your app, allowing you to fine-tune the flow or process.


An impression is the term to indicate that an ad was seen.


In-App Purchases refer to real money purchases which can be made within an app. These can be used to unlock certain content or buy additional in-game currency.


The K-Factor is an indicator of the virality of your app, as it relates to current users spreading the word and acquiring new users.
The K-Factor can be calculated as the Average Number of Invites per Current User * the Conversion Rate of these Invites. E.g. if each current user, on average, invites 2 prospective users, and 50% of these invites convert to actual new users, then you have a K-Factor of 1. If the K-Factor is larger than 1, then your user base will grow.


Key Performance Indicator; this is the term for an important metric of your choice, e.g. DAU, to measure the health of your app. Preferred KPIs may be different from developer to developer, and according to the context at hand.


Lifetime value is the term for the total average amount of money a user will bring in during his use of your app.
Life Time Value typically is calculated as ARPU * Average User Lifetime.


Minnows are low-tier spenders, in relation to other spenders in your app. They do not include users who never spend anything at all.


Monthly Active Users is the number of unique users who opened your app at least once in a given month.


In-app messages can be used to inform users of events or specials while they are using your app. These can be general or targeted in response to the user reaching a specific goal.


This refers to the method by which a developer recuperates his or her development cost. Typical forms are F2P with ads, Freemium with IAPs, or Premium app.


Non-Consumables are permanent in-game items which can be earned as collectibles, unlocked or purchased. As opposed to Consumables, their number does not get reduced on use. Examples are typically weapons or cosmetic items.

Push Notifications

Push notifications are messages which can be sent to the user outside of the app. These are usually used to re-engage the user, prompting him or her to return to the app.


The term used for actions intended to bring users back to the app after they have stopped using it.


Retention is one of the key indicators in analyzing the health of your app or game. Retention is measured by comparing user activity over time. Typically you will compare how many of your users are still using your app on the second, seventh and thirtieth day after first starting the app.

Sticky Factor

See Stickyness.


A trigger is a setting, sent from a back-end service, to initiate an action in the app. E.g. this can be used to unlock seasonal events, change difficulty or the rate at which consumables replenish.

User Segments

User segments are users which are grouped by similar metrics, e.g. language, age, spending, etc.


User Experience. This refers to the ease of use, flow, aesthetic, etc. of your app or game. Ideally the UX should be tested and polished as much as possible to give your app the best chance of becoming successful.


Each time a user opens your app, is seen as the start of a session.

Session Length

The length of time a user is actively engaged in your app or game during one session.

Split testing

See A/B testing.


This is an indicator of engagement.
Stickiness or Engagement is calculated as DAU / MAU.


If you have a fun and engaging app or game, then users tend to promote it to their friends and acquaintances, thus contributing to the virality of your app or game. See K-Factor.


Relative to all your users, whales are your highest spenders. In F2P apps/games, these usually make up a small percentage of your user base, but contribute a large proportion of your revenue.