On Saturday, leaked screenshots of Windows Phone 8.1 developer build surfaced on the internet. New features spotted on the prototype Windows Phone include the ability to close apps from the notificaton center the multitasking window, Datasense and the ability to sort your most used apps. The screenshots were taken from a Lumia 920 bought over eBay by Chinaman28, a Reddit user. The device however had all the indications of being a prototype not meant for public eyes. According to Chinaman28’s thread on Reddit, the letters MSFT had been etched to the back of the device and when booting, the phone displayed the words “not for resale” in red. Microsoft has since contacted the buyer, requesting that they return the device while compensating him for it. Chinaman28 will also be receiving a new Lumia 920.