Update June 18, 2020: Microsoft has stopped accepting Windows Phone 8.x XAP packages. You can no longer publish new Windows Phone XAP packages for new or existing apps. You can continue to update existing Windows Phone apps with UWP packages for use on Windows 10 devices, remove XAP packages from them, or make other updates, such … Continue reading Important dates regarding apps with Windows Phone 8.x and earlier and Windows 8/8.1 packages submitted to Microsoft Store