Barron's algebra app

This is the second app I found by Barron's but it is for algebra.  The first level is just reviewing the use of positive and negative numbers.  It has three. Quiz levels and you must get 80% in order to unlock the video game and move up to the next level.  Each level has 20 questions and again the program does not tell you which problems you missed.  This maybe due to not having a large base of questions to choose from.  

I think not telling students which problem they missed is not helpful but it does make them check all their work especially if they do not like figuring out where they made the mistake.  I see some positive uses for this app in my classroom.