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 Which platforms or devices are your apps available on? I bought an app for iOS/Android. Do I have to buy it again for the other operating system? Do your apps require wifi or an internet connection? I'm trying to buy but the transaction won't go through. What should I do? We have lots of devices. How many copies or licenses of each app should I buy?