How to detect in iOS webapp when switching back to Safari from background?

Question

How can I build a webpage which is able to monitor when the page gets the focus, especially when Safari is in the background and the user switches Safari back to the foregro

Answer 1

Use the pageshow and pagehide events.

https://developer.apple.com/library/mac/documentation/AppleApplications/Reference/SafariWebContent/HandlingEvents/HandlingEvents.html