It's nemo.

Currently as we have a workaround for the battery, in my opinion, there are still 2 showstopper bugs which prevent to use Sailfish as the main OS on my N9:
- no way to sync a Google calendar through CalDav. This is not N9(50) specific, this is a limitation of the current Sailfish, shame!
- Keypad doesn't work during voice calls.

Having these fixes would be great!