Well, the medium term plan is to improve my not-horrendous French and my basic Spanish and Italian, but I'm particularly interested at the moment in Urdu. And there don't seem to be any decent courses in that, but from what I understand if you can do Hindi you can do Urdu - except the scripts are entirely different. Hence veering towards Rosetta Stone, which is noises and pictures, over Duolingo which has a lot of text.
Hence the question - not really "are there any other apps?", but more "has anyone had success with this particular one?".