Addition with an iPad
Here is a simple activity: two kids, counters, and an iPad app.
We use the Math Magic app in my class to work on the basics of addition. I say the basics because the learning that occurs is not always addition. Having kids put together two groups of numbers and count the total does not mean they are all truly learning addition. Despite that I still love this activity. My kids that are not quite ready to understand addition are still working on counting, number recognition, one-to-one correspondence, and learning how to keep organized. They are also getting feedback on their answer every time they pick a number. Those kids that are ready for addition are getting great practice. When we play this game they are almost always in pairs. Sometimes I group the kids with a friend at a similar ability and other times I pair lower/higher kids together. I see value in both those groupings.
I am sure there are many apps that would work for this, the app itself is really not that important. I like Math Magic because it is simple and it allows me to adjust the number range for the problems (see below). The only setting I really use on this app is the minimum and maximum number slider. I adjust it as need for the group playing.