I appreciate your app, and my toddler likes it.
My device is an Archos 5 internet media tablet. I don't have an sd
slot, however, I have a large internal hard drive.
My first suggestion would be to set an OPTION as to where to store the
extra tiles (SD card, or choose a directory, etc.)
My second option would be to be able to select tiles off your device
from a picture folder (if they have to be a certain size to work, just
let me know and I can create a special folder for that).
If those two both worked, I think this would be a good paid app (for a
couple bucks, etc.).
You could offer two versions, etc. a free, and one with those
options.
Thanks