Yoyo Test is an iPhone app designed by Rudolf Fernandes for assessing stamina levels akin to sports like soccer and basketball. The app facilitates the Yo-Yo Intermittent Recovery Test and the Yo-Yo Intermittent Endurance Test, Level 1 and Level 2, following the methodology defined by Jens Bangsbo of Copenhagen University in 1994.

It provides various features including voice cues or customizable ringtones, countdowns for shuttle halfway point and speed level changes, recovery time display, distance covered, elapsed time, and final results like the achieved level and total distance run. The app offers an estimated VO2Max for Recovery Level 1 if a minimum distance is covered.