1) Open the iOS App Store or follow this link and skip to step 3.
2) Search for 'infinit' from the App Store search tab.
3) Tap the Get button from the search result, then tap the Install button.
4) After the app finishes downloading, tap the Open button
5) Read the tutorial to discover how to use Infinit.
6) When asked if you already have an account, tap Yes.
7) Enter the login details you used on your other device(s).