We are developing for the iOS platform - but it's only one of seven platforms we're developing for (Windows, Windows Phone, Windows RT, Mac OS X, Android, Chrome - and iOS of course). Unfortunately iOS is the only platform which did not receive any update since many months.
In the past weeks and months we have been working hard on a much improved (and major overhauled) version of Boxcryptor for iOS. It will be available as beta at the beginning of next year. You can signup for it here:
I'm sorry that you have to wait so long.