The Gospel Media app has a good collection of videos, images, and music, and its current focus is being a resource for teachers (pulling together media for presenting in a class or family setting). There's some overlap with content in Gospel Library and Sacred Music, and it's not comprehensive as the other apps (for example, the general conference videos in Gospel Media don't go all the way back) – but it does have some media that isn't in the other apps. If you're looking for "inspire me" media content I'd recommend Latter-day Saints Channel and/or Sacred Music. But I think it wouldn't hurt to install and play around with Gospel Media, since it's a free app – if nothing else, learning how to use it so you can help others use it.
The Gospel Media website has the same content as the app:
https://www.churchofjesuschrist.org/media?lang=eng
