Window 10 Mobile may no longer be supported, but that does not mean you have to retire your Lumia 950 or 950 XL.
Developer José Manuel Nieto has created a tool which makes it super-easy to install Windows 10 for ARM on your Lumia 950 or 950 XL, meaning in theory you should be able to run any win32 app on your handset.
You will first need to unlock your handset using WPInternals, then, while your phone is connected to your PC, download Windows 10 ARM64 image, WoA installer and core packages from here. After downloading the files, run the tool, import core packages from the advanced settings, and follow the on-screen instructions to boot the OS on your phone.
As can be seen from the screenshot, both dual-boot and single-OS options are available for the install.
The art and science of running Windows 10 on the Lumia 950 XL have advanced a lot over the last 6 months, making for an almost usable experience.
The installation now supports WIFI networking, features accelerated graphics (which results in a smoother UI and less power usage), the speaker and microphone work, as does Bluetooth, USB-C, the SD card slot and the ambient light sensor.
In addition the installation now also supports the S0 power mode, meaning the device will drain almost no power while the screen is off.
The project is being actively pursued by a large team of developers and enthusiasts, with the holy grail, of course, full WLAN connectivity.
Of course it is fair to ask what you will do with full Windows 10 on your phone, but in the end, was this not the eventual holy grail of Windows 10 Mobile?
See the process of installing the OS (in German) in this video by WindowsArea.de below: