This is a nice little free app that can be used in the high school to scaffold struggling learners. I used it in my Geometry class. I had them work with the Ratios and proportions
then I had them choose the compute ratios.
The students had trouble with finding fractions of a ratio such as you have 5 gallons of milk and each container holds 1/5th of a quart, how many containers do you need. If you are wrong, the app tells you the correct answer but it does not show you how to get the correct answer.
This does tell students how they are doing overall and it does have a limit of questions that each student can do every day. I became aware of the limitation the first time I tried the app.
Over it is a good practice app.