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Hi, we're developing an app which requires login. The login is managed on our Drupal server and allows both login on site and in app. Now we want to use in-app purchase to allow users to sign up directly in the app by buying a subscription. user signup in app (choose subscription) purchase/payment is handled by apple User credentials are added/created on our server?! Step 3 - what is the right way to do this? Is there a guide somewhere?

We need to add text editing and formatting to our app. We both have inline formatting like bold, italic, underline as well as paragraph styles like heading 1, 2 and 3. We have multiple pages showing the text in a text area. I thought this would be a simple task however it is very complicated to apply styles and display them.Is is there a extension or module I can utilize to have core text formatting functionality added to my code?