In the old Windows Phone Store that was available through a desktop browser, you could list all the apps you had downloaded, and push an app to your phone over the air.
Now with the Windows 10 store, you can only list the app that you have *purchased*. If the app was free, then it doesn't show up.
Quite regularly on the Insider programme, even with restoring from a backup, not all the apps you have installed previously are reinstalled by the restore, so knowing what apps you had on the phone is very useful, even if they were free (especially if they were free - most of mine are!)
Now with the Windows 10 store, you can only list the app that you have *purchased*. If the app was free, then it doesn't show up.
Quite regularly on the Insider programme, even with restoring from a backup, not all the apps you have installed previously are reinstalled by the restore, so knowing what apps you had on the phone is very useful, even if they were free (especially if they were free - most of mine are!)