What version of iOS or Android operating system do I need to use Tactus Therapy apps? May 21, 2019 23:51 Updated Follow Current minimum iOS version: iOS 9 Current minimum Android version: 4.1.x Related articles I bought an app for iOS/Android. Do I have to buy it again for the other operating system? Which platforms or devices are your apps available on? I'm trying to buy but the transaction won't go through. What should I do? Do your apps require wifi or an internet connection? We have lots of devices. How many copies or licenses of each app should I buy?