iPhone White Box around Screen IOS8.0.2 Iphone 6

Hi all,

I get a white box on my iphone 6 screen. If I reboot, it goes away, but reappears randomly, sometimes around the whole screen, sometimes a moveable box about a third of the size of the screen.

I am sure it is an IOS issue, but cant find anything about it.

Anyone else get this issue or know how to fix it ?

Pic attached.

 

possibly fixed

just switched off Accessability/zoom, and it has now gone. if i switch back on, box still gone