I am using Xamarin to develop an Android/iOS application. The client has a requirement where, if the device gets within a distance of a predefined location, the app will send them a notification.
I imagined that I would need some kind of background task running that will check their location at regular intervals, sending them the notification if close enough. However, documentation like Introduction to Backgrounding in iOS and Creating Android Services seems to talk about background tasks in the context of an already running or suspended app, unless I am misunderstanding. I need this task to be running even if the application is closed and not in use.
How can I create a task in my Android and iOS application that will check the device location periodically, and send a notification when near the predefined location?