You can buy Football Manager Mobile 2018 from the iTunes App Store via this link:
Your device must be running iOS 8.0 or later. This means the earliest generation of devices that can run the game is iPhone 4S, iPod 5th Generation and iPad 2nd Generation.
Football Manager Mobile 2018 will require up to 1.2GB to install and run (depending on device).
Please post details in the bugs forum for us (use a new thread) and we'll do our best to talk you through resolving any problems you might be having with installing the game.
Such issues are rare, however they're also device specific so we may need to ask you a few questions in order to resolve them.