There is an entire community of users who can't resist exploring new techniques to install operating systems on phones that haven't officially received any support to run said OS. To that end, Microsoft enthusiasts have been attempting to bring different desktop versions of Windows to Windows phones.
Earlier this month, a Lumia 830 powered by Windows 10 was showcased, along with Windows RT installed on a Lumia 950. Most recently, however, a project to properly run Windows RT 8.1 on a Lumia 640 XL was initiated by Twitter user, @imbushuo. It seems that his project has been making new strides, with GPU support on the processor and audio over Bluetooth now being made available.