You can think of it as another version or PE with some nice modding and customization options included. The latter, in particular, made a compelling proposition as it enabled you to play anytime and anywhere with Minecraft Pocket Edition(PE), and Minecraft Launcher is another way to play it. It started as a PC game but quickly grew in popularity and received console versions and a mobile port quickly.
Minecraft is one of the greatest games ever made and is enjoyed by millions of players worldwide.