Mobile applications: Main definitions and vocabulary

AppStore: An online store for downloading applications. Major app stores include Apple’s AppStore, Google Play Store, and Amazon AppStore.

ARPDAU: Average Revenue Per Daily Active User. It is one of the most common monetization metrics in the mobile space. This gives developers a sense of how their application is performing on a daily basis.

ARPU: Average revenues per user. It is normaly a monthly metric
ARPU = LTV (Lifetime value) / (Avg no. of months a player plays your game)

ARPPU: Average Revenue Per Paying User. It is the average revenu spent by a paying user in a game / application.


CAC (Customer/User Acquisition Cost): All the money spent advertising to prospective players, divided by the number of new players you were able to acquire during that same time period.
 
DAU/ MAU: The ratio DAU/MAU (Daily active users / Monthly active users) is used to measure stickiness of your users. How well the game is capable of retaining the players is indicated by this metric. In a way it exhibits the potential of the game to drive engagement and make it extremely compelling for the players. How many of the users that have visited the game in the past month also initiated a session today?
A game with a strong DAU/MAU ratio will be able to maintain a value over 0.2 for an extended period of time. Be careful comparing this between games: when running a user acquisition campaign, the ratio will be skewed upward.

K-factor: measure of viral growth. A k-factor of 1 means you’re gaining one user through one existing user, and your app is neither growing nor declining. A k-factor of less than 1 means that your app requires marketing efforts, else it might run out of users. While a k-factor greater than 1 means that your app is growing exponentially


LTV: Lifetime Value. It is the total revenue that a user will spend during its entire lifespan in a game / application.

Positive Unit Economics: This means you are profitable when it comes to app monetization, since it indicates your LTV is greater than CAC (Customer Acquisition Cost).

Retention: retention is defined as a calculation of active users  over time. Retention is normally estimated after Day 1, Day 3, Day 7, Day 30, Day 90...


Sessions/DAU: This metric refers to how many times the average Daily Active User (DAU) initiates a session in a game / application.
A strong number of Sessions/DAU is usually around 3, but it really depends on the genre of your app.

SDK: Software Development Kit. Short for software development kit, a programming package that enables a programmer to develop applications for a specific platform. Typically an SDK includes one or more APIs, programming tools, and documentation.