Those of you who own the Windows 10 Mobile based smartphones must know about the Windows Continuum feature of these devices. This feature allows you to boot into the desktop version of Windows 10 when you connect the phone to a larger screen. Now the open-source community has come up with a similar feature for the Android devices in form of the MaruOS. The MaruOS is a firmware based on Android 5.1 that ca be used to run the desktop version of Debian Linux on a larger screen while running the Android on the mobile phone screen at the same time.
The Maru OS is available only for the Nexus 5 devices as of now, but it is matter of a few months for the open-source community to port the ROM for other devices. The ROM is still in the beta stage and the developer wants you to sign-up for the newsletter before you get the download link for the ROM.
Before you can flash the ROM, you should have installed the ADB and Fastboot in your PC. After getting the ROM, extract all the files to a folder and give the following command to reboot Android into fastboot mode: adb reboot bootloader.
Once the device has rebooted into the fastboot mode (the screen will display fastboot text on it), you can give the command flash-all to flash the firmware. This will take some time to complete and after this you can reboot the phone back into the normal mode. You should know that all of your data would get overwritten so you may want to backup your important files before flashing the ROM.
Now, you can use the Android 5.1 on your mobile phone. And if you want to use the Debian Linux on a desktop PC, just connect the phone to a large screen using a USB-to-HDMI adapter cable. They recommend a special cable that also allows for a travel charger to be connected in the middle so that the battery does not get discharged very fast. The data stored on the memory of the phone or a microSD data are accessible via both environments. The Debian Linux will stop running as soon as you plug out the HDMI cable.
You can join MaruOS community at http://maruos.com/.