Telerik UI for Xamarin doesn't have any application lifecycle helpers. You could try checking to see what Microsoft documentation - Xamarin Forms app Lifecycle
Ultimately, for help with general Xamarin and Xamarin.Forms development, I recommend posting such questions in the Xamarin Forums
(using Xamarin tags). This forum is specific to the Telerik components, so you wouldn't get much interaction for general Xamarin topics.
Lance | Technical Support Engineer, Principal
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