"Yay! I get to learn my shapes!"
I have a pretty cool app on my iPad for ages 2-8 called Agnitus which the kids play from time to time that has practice in colors, shapes, foods, and more. I like it because it has many free games, sends you progress updates on your kids' learning, but I think sometimes my daughter messes up on purpose. :)
This ad on YouTube even claims its great for the kid who wants to touch everything, which certainly describes my boy.
My kids loves their Kindle time as much as the next, but their kinesthetic learning styles demand tactile experiences that a tablet (as much as it improves the mouse) cannot provide as well as tangible, spatial things.
|Montessori Wooden Shape Board, Fraction Sorter on Amazon|
I don't want to condone educational hoarding, but don't throw out the old manipulatives with the bath water when you get that iPad cart.