Ho Ho Ho!

Santa brought the children iPod touches this year--remember back when I was pining for them to have these? You'd think that's the only gift they opened--I've never seen them so silent and absorbed in what they're doing.

So far, I've downloaded Angry Birds, Doodle, Handy Manny Workshop, Itsy Bitsy Spider, Preschool Connect the Dots, Talking Tom Cat, Tesla Toy, Toddler Fun Phone, Toy Story 3, and Wheels on the Bus. They all seem pretty easy for them to figure out, to varying degrees. Any other suggestions for educational apps for a six year old and smart three year olds with limited fine motor skills?

Note: I'm particularly interested in musical instrument apps. I'd like for them to be able to tap on piano keys or strum guitar strings. I know a piano app for iPad exists, but I can't find the magic words to search for anything that works for iPod touch.