Learn X in Y minutes is a great site created by @adambard and hosts hundreds of short programming language tutorials written by himself and many other contributors on GitHub for professional programmers to get up to speed quickly on a new language.
I needed to have access to those great tutorials for some of my favorite programming languages on my phone for offline viewing. So I created this Progressive Web App using Ionic 2 framework. You can also build and install this app on your device as any other mobile apps.
