The YoYo Fitness Test, developed by TheoryBiscuit, is a free lifestyle app available on Android. It is designed to test your maximal aerobic endurance through the popular intermittent recovery test and endurance test, also known as the "Beep Test." This app allows you to test yourself and find your Vo2 max using the Intermittent Recovery test 1 & 2 and get a grading.

The app has undergone updates as recent as January 2022, including a fix for the crash when deleting records, UI improvements on smaller screens, and minor animations. The app now includes a group run feature, allowing up to four people to record their results. Additionally, graphical data has been added, reducing crashing and locking buttons during the run, and a share button has been added. The app also has pre-level start and end warning beeps, motion detection via accelerometer, and more setting options.

Overall, YoYo Fitness Test is an excellent app for those looking to test their endurance and improve their fitness. Download it now and test your limits!