There is an infinite number of AVR website that has configuration wizards for UART, Timers and SPI, but I didn’t find an iPhone application that can do something similar. So I developed an iOS application that lets you setup the AVR SPI easily, email this configuration, and also understand what each bit of the SPI registers does. The application is called AVR ISP and soon it will be available in the App Store. Hopefully the next version (1.1) will have code generation in C and ASM, and not only for the setup, but also including functions for handling the SPI interface.
Here I show some of the screenshots of the app. And as soon as Apple publishes the app in the Store I’ll upload the link.

UPDATED: Apple has approved AVR SPI and now it’s ready for download from the App Store. You can find it by just looking for “AVR SPI” or using this link to iTunes