There isn't really an easy way to run Android applications on the desktop. There are virtualization tools like AMIDuOS and Bluestacks, but those run Android apps inside a fixed window and can be slow at times. Anbox is a new project, currently in the Alpha stage, which aims to run apps alongside your normal desktop applications - as long as you use Linux.

Anbox uses Android 7.0's freeform mode, which means that app windows can be resized and moved around. In addition, Anbox doesn't use virtualization or emulation - the Android kernel simply runs in a sandboxed Linux subsystem. This does mean you have to give it full root access and install some additional kernel modules, but it's still very cool. You also have to use ADB to install third-party apps, since there's no app store built-in yet.

Anbox is fully open-source, and available as a Snap package for easy installation. Currently, only Ubuntu 16.04 LTS or later is officially supported.