This timer meets the needs of amateurs as well as professionals. It was designed to be flexible and highly customisable so it can be used for all kinds of trainings. - Runs and plays music on background.- Universal app, works on iPhone and iPad.- Max interval duration is 99 hours 59 minutes and 59 seconds.- Max number of sets is 999.If you have enable Track Location option please note: Continued use of GPS running in the background can dramatically decrease battery life.