MathU 12D v1.3.1 for iPhone
MathU 12D is available exclusively via Apple's App Store. It is currently available for $5.99 USD. Use the iTunes Store or your iPhone to access the App Store and then search for "MathU".
Like all iPhone applications, the only way to get MathU 12D installed in your iPhone, iPod touch or iPad is via the App Store. To purchase, open the App Store within iTunes or on the device. Search for "MathU 12D". Installation happens automatically when you purchase MathU 12D through the App Store.
When you click the App Store icon or the link above, the App Store will automatically open within iTunes 8 or higher. If this does not work, open the App Store on your iPhone or iPod touch and search for "MathU".