Hands on equations lite

When I first downloaded this app and opened it I was a bit disappointed with it because it only had a video for each of the three levels.  All other functions were locked and you have to pay for an upgrade if you want access to all the functions.  After some thought, I decided it is not a bad thing.  I watched the the first video and liked the way it used a pawn and a balance scale to explain solving for the variable.  This gives students a new way to view the process and it is a way to differentiate my instruction.  In addition, I can have students rematch the video as many times as they need.  Hmmm I could use this app as part of a center.
I know they use centers in elementary school but not as much in high school.  I just realized I could use many of these apps as part of a centers set up.  I have a classroom set of iPads that I could set up into centers using the app.  I would have to arrange for instructions that would have students do more than just watch the video.  They might have to answer questions, do some of the problems out of the video.
If you have used mobile devices as part of centers, I would love to hear from you.

Middle school Algebra 8th grade.

The app shows up as Math 8 on my ipad.  it is an app that has a lite version and a paid version.  It has a monkey on the face of it and is a game where you tilt the ipad to move the monkey to the right or left.  If you get the monkey in the right spot, it gives you a problem. After 8 problems it gives you a score.  Each of the 4 topics has 3 levels  and you can do all three levels to become quite familiar with the process.  The four topics that come with the free versions are 1.  Words to expressions, 2.  Evaluating Expressions, 3 solving 1 step equations and  4. 2 step equations.  If you purchase the paid version, you can get linear equations, multi-step equations, solving inequalities, systems of equations, rational equations and exponential functions.
I think the free app will really do lots of good in my class as I can see having my students practice changing words to expressions using this app.  Since many are ELL, this will allow them to practice the topic in a fun filled way.  Actually all 4 topics are ones that my students need practice in.  I can see even using this app in Algebra II as a review for solving one and two step equations.  I like what it has to offer and I can use it for Pre-algebra, Algebra I and Algebra II to reinforce the skills. 
I think my students will enjoy using this program and will practice the skills since it is a game and it will prepare them better to do the actual work associated with the topic when I finally hand out practice sheets.  The company that makes this also makes a middle school grade 7 and 6.  I looked at those and just looking at them, grade 7 has students practicing using negative and positive numbers. 
I plan to download the grade 7 free app to check it out.  I just discovered there is a way for students to e-mail scores to the teacher so that I can monitor their progress.  The full versions are 99 cents and allow you to access all levels, not just the first four.  Furthermore, they are labeled the same except with the word pro. 
I am going to recommend getting this for school in the fall and I am going to integrate it into lesson plans.