I am using Window phone 8.1 Nokia Lumia 625. It is almost perfect if I could set up ringer tones for the divided groups at my phone book and activate auto answer in coming calls function when using my head sets and blue tooth head as well. You prompt and sincere help would highly be appreciated.
Truly yours
I am running 8.1 GDR1 on my 920 without Cyan, and there is little to no lag. I did have a tiny bit with just 8.1 but with the GDR1 it seems to have alleviated it.