Apps built with iOS 10 and Xcode 8 can crash when the user accesses API's such as Camera, Calendar & Contacts

Apps built with iOS 10 and Xcode 8 can crash when the user accesses API's such as Camera, Calendar & Contacts. 

After some research, this is because iOS 10 and later required the following keys that have been introduced back in iOS 6!

My App crashed at this line: 
var accessGranted = DeviceHelper.Current.EventStore.RequestAccessAsync(EventKit.EKEntityType.Event) 


Resolved it by: 
Edit the info.plist:  Privacy - Calendars Usage Description
Date type = string.
Value = Please provide the reason why you app ask for the calendar usage.

Doc ref:
https://developer.apple.com/library/content/documentation/General/Reference/InfoPlistKeyReference/Articles/CocoaKeys.html

https://developer.apple.com/library/content/documentation/General/Reference/InfoPlistKeyReference/Articles/CocoaKeys.html#//apple_ref/doc/uid/TP40009251-SW15