Perfect MP3 player for language learners

If you're learning a language, I have found the perfect MP3 player that is specially designed for language learners (and for sports). The 10 sec back function is very handy for repeating. I also love the design of the skin, it looks very cool and practical. It seems that it is a good app, also due to the amount of positive reviews. The sliding command when the phone is in your pocket also work well. https://play.google.com/store/apps/details?id=cz.nom.handyMP3playerTrial