The download button opens the iTunes App Store, where you
may continue the download process. You must have iTunes installed with an
active iTunes account in order to download and install the software. This
download may not be available in some countries.
From Silicon Labs:
Jumpstart your iOS accessory development with the latest low-cost development kit from Silicon Labs! Use this app to easily interact with the Silicon Labs MFI-SIM3U1XX-DK Accessory Development Kit. Control LED indicators on the kit's development board and in turn capture status of capacitive touch buttons, slider, and knob positions. The MFI-SIM3U1XX-DK Accessory Development Kit is controlled by Silicon Labs SiM3U1XX microcontroller. The board provides a streamlined, low-cost platform for developing device-powered dongles, entertainment appcessories, game controllers, and graphic-rich audio docking stations.Note: requires the MFI-SIM3U1XX-DK from Silicon Labs. Visit www.silabs.com/mcu for more information.Features Demonstrates interaction between iOS app and SiM3U1XX 32-bit microcontroller Use app switches to turn on and off LED indicators on the board See status of kit capacitive touch buttons, slider, and knob position on the app screen See board configuration information in the app console log