- "Keep tabs on the ones you love."
- — Motto
Grand Theft Auto IV
In Grand Theft Auto IV, the app is mentioned in radio commercials. The commercials state that it's an app used to reveal the exact location of your family, and that it's just for kids. A man commenting on the app in the commercial claims that the app tracks down a microchip implemented in his children's brain.
Grand Theft Auto V
In Grand Theft Auto V, the App appears as a heart that at the same time represents the letter "i" in the logo. It consists of a blue screen and lines with a sonar that tracks a red dot (the objective). When the player is close to the dot, the scales are zoomed to indicate an approximation. The sonar is oriented by a vehicle, so if the red dot is in the middle, the vehicle must travel on a straight line to reach. The beeps also become more frequent.
Unlike Grand Theft Auto IV, where the app is used, it seems to track down weak signals which get stronger the closer the player gets. Also, in Fresh Meat, Lester Crest tells Franklin that the app is used to track down a microchip in Michael's cellphone, which indicates that the manufacturer of Trackify no longer implement their microchips into people's heads. Similarly, in Pacific Standard - Vans, the same app is used to locate four Post OP Boxvilles, implying that the change was made before the events of GTA V. With this info, it is clear that between 2008 and 2013, Trackify changed its tracking method.
The Trackify app in GTA V is slightly different in appearance that what it is in GTA Online. In GTA V, there is a red dot on the screen that features an arrow on top of it, pointing in the direction needed to go, and disappearing when close to the target. Whereas in GTA Online, the arrow is missing completely, and the app logo to open it, is different. It is most likely that Trackify has been updated to a new, more user friendly version by the events of GTA V. This is referenced by Lester during the GTA: Online heist mission, "Pacific Standard - Vans".
Trackify takes a larger role, being used to track down debris, nuclear waste, and Michael De Santa in Fresh Meat. In these cases, the Trackify App appears on the down-right corner, next to the Internet App.