What does "IAP" stand for?
The initials IAP refer to in-app purchases. You will normally see tech websites and blogs refer to IAPs and "timers" when talking about mobile games available in the Apple App Store. An in-app purchase is a micro-transaction required by an app or game to purchase additional content after it has been downloaded. IAPs are a source of controversy since some users claim they ruin the experience of mobile gaming. Apple has also been sued over children racking up thousands of dollars on their parent's credit cards due to in-app purchases. This is why Apple requires you enter your password every time you make buy anything within an app. Apple also added IAP labels under the download price of each app and game in the App Store with the release of iOS 7.1.1.
A "timer" refers to games that make you wait a specific amount of time before completing an action. Timers normally go hand-in-hand with in-app purchases on "freemium" titles in the Apple App Store. "Freemium" refers to a game that is free to download. The word "freemium" is normally used in a negative way to describe games that require a lot of timers and IAPs to complete. These games are considered a drag by the gaming community and are normally boycotted by hardcore gamers. However, there are a lot of freemium games available in the App Store that are not bogged down by IAPs or timers.