[DarkMuse]

I've seen their apps, I don't use them though, as they require GAPPS.

Even on the web is fantastic. I'm speeding through C++ to get ahead in my class and so far, so good. There's even a shortcut option if you know some stuff already. You take a quiz and if you pass it, you can skip those modules. At the end of the course, you get a certificate as well which would serve nicely as a "hey look employer, I know this language!"