Do Windows Phone 8 apps run on Windows Phone 8.1

Question

If I am to publish an app to the store that targets Windows Phone 8, will Windows Phone 8.1 users be able to install it to their devices?

Answer 1

Yes, Windows Phone 8.1 users can use Windows Phone 8.0 apps. Because it has Backward compatibility. Apps created to target Windows Phone 8 continue to function on Windows Phone 8.1 devices without being republished.