The drop-off rate of end-users with a Windows Phone migrating towards Android or iOS is rather ginormous. Whenever users get a chance to upgrade, they move on-wards. Only 20% stays loyal to Windows Phone, 60 percent moved to Android, 15 percent moves to iOS.

These numbers come from Ericsson in their Mobility Report, and yeah .. are pretty darn significant.

Androiod users are the most loyal as 82% stay on that platform after their purchase. For iOS that is 73%. According to the report a new Windows Phone model is only suitable for 20%. Where the last 5% stays is not clear in the rapport. The rapport also mentions that high-end smarphone users are much more loyal to their OS opposed to a low-end model. 

Ericsson uses anonymous data it gathers from more than a hundred networks worldwide.

Check that report right here.