Fun app, but not 700MB

My kids enjoy this app and I would love to put it on the old iPhone I let them use, but it installs at 1.4GB, not 700MB. Even on iTunes it shows that it will install at 1.3x GB even though the physical file size is indeed 700MB. I have no idea what adding the Math Pack would do, if anything (for all I know that extra 700MB is the locked levels). Anyway, its too large to put on a 16GB device if I want to give the kids variety. That could be a dozen apps or about 2-3 hours of video.

Jmg1674 about Mickey's Magical Math World