This app was mentioned in 2 comments, with an average of 1.00 upvote
Try out Beginner Arabic or StartfromZero_Arabic apps. Its a good way to get to know the common words and phrases in Arabic.
https://play.google.com/store/apps/details?id=com.shex.startfromzero_arabic
https://play.google.com/store/apps/details?id=com.shex.beginnerarabic
As far as the basic Arabic vocabulary (i.e. MSA) is concerned, you could try the StartFromZero_Arabic app, Beginner Arabic app and Arabic Locker app.