Just this afternoon my phone started going "back" to whatever app was last opened.
It appears to do this when refreshing the tiles.
The problem is, when you close all apps it just flashes, says "loading" then reloads the start screen....to which it flashes and says "loading" then reloads the start screen....then it flashes and says "loading" then reloads the start screen....then it flashes and says "loading" then reloads the start screen....to which it flashes and says "loading"....over and over. I've soft reset, rebooted, turn on airplane mode etc. nothing changes it.
If I sit on the all apps screen, we're fine. If I sit in an open app, all fine.
Edit: 950XL DS
I also noticed that mobile task manager (which requires dev mode enabled) no longer recognizes dev mode as being enabled. I follow the directions on it and validate that it is setup correctly yet no joy.