I found this line of apps by HUP. The one I am looking at is HUP algebra. It is a nice app which could be used to help flip the class and have students use the app at home. It has several sections starting with "What is algebra?". Then it has sections on solving single step equations using addition, subtraction, multiplication, division. Each has a pictorial example using tiles, a written example and you can try problems. There is a section on solving multi-step equations and on solving equations with the distributive property. All sections have practice problems. I like this app as I can use it to flip the class or I can use it to scaffold some of my students who need additional help or practice. It is free at iTunes. I just got a Nook and I am starting to find neat apps there so I will review some of those.