Learn NMR FID
Learn NMR FID is a great teaching tool to learn the basics of NMR data collection and processing. Use simulated free induction decays (FIDs) and spectra to see apodization, noise and relaxation effects. Move peaks and see how the FID changes. Real and imaginary FIDs prior to and after processing are displayed as is the resultant spectrum after the Fourier transform.
There are more science apps for iOS on the mobilescience site.
I also thought I’d mention this framework that was brought to my attention recently. There is a trend to move massively parallel tasks to the GPU, GPU Image is a framework (BSD license) that simplifies the creation of GPU filters. This framework is built around OpenGL ES 2.0, so it will only work on devices that support this API. This means that this framework will not work on the original iPhone, iPhone 3G, and 1st and 2nd generation iPod touches. All other iOS devices are supported.