We've given you a full beginner's guide to coding, and this app would be a decent supplement. It includes seven major sections, and you navigate through quick lessons in each one. At the end of the lesson, you're met with a small quiz to test your knowledge.
This is ideal for learning at your convenience, and while it might not be a replacement for complete lessons, it's a solid complement. The first set of lessons are free, and you can pay $3.79 for all the remaining lessons.
Right now, the app is only available on iOS, but an Android version is coming soon. On Product Hunt, Lrn's founder says they hope to include more programming languages in the future, too. Check it out for yourself at the link below.
Lrn [Apple Store]