I a'm running an uwp app on Rasbperry Pi 3 with Windows 10 IoT OS via Visual Studio Remote Machine and Release is selected.
The problem is how to save settings I have made and use the same settings when run same UWP app later.

How is it done? I can read the settings from the text file from
Windows.ApplicationModel.Package.Current.InstalledLocation;
But of course I can't save any changes to the same text file.
Where exactly should I put the text file if I wan't to save changes to text file?

But perhaps I can use this
Code:
Windows.Storage.ApplicationData.Current.LocalSettings;
But how do I check if there is no value stored and put instead an default value?

With this I am trying to save these settings it doesn't work.
The point with this is that I can use these same settings when I run the same uwp app again.
Code:
var localSettings = Windows.Storage.ApplicationData.Current.LocalSettings;
localSettings.Values["setting1"] = textBlockDelayValue.Text;
localSettings.Values["setting2"] = checkShow;