UpdateVersionStartupTask.cs

public class UpdateVersionStartupTask : IStartupTask
{
    public Task<bool> CanRunAsync() => Task.FromResult(true);

    public Task RunAsync()
    {
        //TODO: Do Store version code here, can't do it since this app is not in the store
        return App.Current.MainPage.DisplayAlert("New Version", "There is a new version of this app available. Would you like to update now?", "Yes", "No");
    }
}