i want to share another efficient and free way to learn vocabulary on your mobile device:

i got me a free app that allows me to download decks of flashcards from quizlet.
so just type in your app search "quizlet".
i have tried three apps:
a+pro, flipcards and flashcardlet.
the one with the best use is a+pro but i am no sure if its still free.

so now that you have the app you go to www.quizlet.com and create or import your cardset. (quizlet is also free.)

now you just import your freshly created set of cards into your app and you have your own study device on the go.