Android smartphones and tablets can most definitely serve as general purpose computers (for developers on the go at least). My daily-driver is loaded up with the latest bash, python2, python3, gcc, openssl, ssh, busybox, etc. I'd never carry around a laptop, but with a phone it is always on me so I can get right to work anytime I have a few spare minutes. Just pull up a terminal and ssh into a development box or work locally. Its as easy as can be... You can even run a full Debian image or distro like XFCE in the background if need be. I usually just ssh in, but you can also connect over VNC for desktop use (this is generally best on a tablet). It works really well for me anyways.