This is for the on-the-go sorcerer. None of these apps cost money, they do have ads. I set the frequency in AdMob to be one every 2 minutes per user. And the ads do not load on every page. So it is not too bad, but ads are still there.

https://play.google.com/store/apps/dev?id=7846480248901593885

These won’t teach you theory or things like that. There are some practical tips and explanations. If you are a beginner, these will probably only irritate you. The FAQ pages are less than user-friendly. On the other hand, the price (free, sort of, there are ads) is right. If you read the FAQ pages, even if previously you knew very little, you can still get started.

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