MaruOS
MaruOS is a Linux desktop distribution that it can convert your Nexus phone to a desktop computer. MaruOS is created from Debian sources and it’s supporting wide range of applications such as LibreOffice.
You have too accept the risk of installing another OS on your cell phone but then you have portable powerful desktop. You need to have a micro-USB to HDMI converter for screen connectivity.
Keyboard and mouse will be connected to smart phone via Bluetooth.
You can download this OS from this link: https://github.com/maruos/maruos/releases