Well, the app has three levels of problems. Each level has 20 multiple choice questions and you need to get 80% to move on to the next level. There is a game associated with each level but it is only accessible after you get the 80%. The problems are good and increase in difficulty and complexity. The bad thing is that the quiz does not provide any feedback to tell you which problems you missed. This is the same complaint reviewers had two years ago and this has not been resolved. The idea is good but the implantation leaves a lot to be desired. This is a free app and if you use it for practice with students working out each problem until they reach the 80%, it does give students some good practice.
Tomorrow, I will take a look at Barron's algebra app.