iOS 9.3 is coming in the Spring and will introduce Night Shift as well as a number of other new features.
iOS 4.1 Restores Field Test Mode
Gizmodo reports that iOS 4.1 has reincluded the Field Test mode to iOS. Field Test mode allows you to get a numerical figure for your antenna strength rather than the traditional bar measure. To get to Field Mode:
- First, upgrade your iPhone 4 -- or any iPhone -- to iOS 4.1.
- Dial *3001#12345#* into your phone [and press Call].
Most customers won't care about their numerical signal strengths, but the antenna strength changes generated a lot of publicity surrounding the iPhone 4 launch due to issues with new antenna system.