How to register for Win8 periodic tile notifications?

Question

I am working on a Win8-UI-App (previously called Metro...) and trying to implement Periodic (Documentation for different methods) Tile Updates (Live Tiles) for the first time.

Answer 1

Periodic updates will continue until they are explicitly stopped or your app is uninstalled. Technically, you only have to do that once. But, the Guidelines and checklist for periodic updates states

Call the StartPeriodicUpdate or StartPeriodicUpdateBatch method each time your app is launched or brought into focus. This ensures that the tile content will be updated each time the user launches or switches to the app.

According to that, App launch and App resume are good candidates for a call to StartPeriodicUpdate.