How old of a phone can I use? December 22, 2024 20:19 Updated If the phone has the latest iOS (Apple) or OS (Android) software, the YO app will work. Related articles How do I connect YO to my phone? Can I use another phone if the current one is not working? What phones can I use to test? Can I skip the 10-minute timer? The YO block doesn’t turn on when connected. What do I do?