Android Question Demo / Trial

Erel said:

Option one: create two versions of your app, one free and one not, and upload them to Google Play.
Option two: create a single version and use in app purchases to open more features.

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1. Are there any tutorials for creating an app that has in app purchases?
2. This would give B4X users a blueprint on how to achieve it so it works correctly the first time. (No point re-inventing the wheel)
3. What features are suitable for in app purchases and what features won't work for in app purchases?
4. How does the developer protect his app from users trying to circumvent in app purchases?