I agree with Apple- I downloaded Duolingo last year when I was searching for language learning resources, and love it. I am using it on my phone and take advantage of its easy interface and fun game style to learn a bit more Spanish.
The app has several levels as well as different types of exercises, from filling in the right word to speaking the right word into the microphone. Once you have completed a level you get a badge!
It really helps that there is an audio component- you need to speak, but the app speaks to you as well so you can hear how the word is supposed to sound.
It is a great recommendation for students who need extra practice. Oh and bonus- it is free!!!!
You can also use it for learning French, German, Portuguese English and Italian.
At Carnegie Mellon University, where he teaches computer science, Luis von Ahn and student David Klionsky thought there should be a way to use smartphones to teach new languages.
See on www.usatoday.com