Regarding "Screen mirror"(referring to built in Miracast app) it's a touch and go matter. It works on some configurations. For example, I have a M8 and mx2 and can get only sound for "screen mirroring" via my Samsung Galaxy Note2 Lte, but it works flawless with my mom's Samsung Galaxy K-Zoom.The whole phone is being mirrored and you see screen duplicated with menus etc. photos and video works.
Then there is the built in "mediacentre" app which gives "Airplay" capabilities , you must enable the service to start with bootup and not only when app is launched. This does photos best in general when in android gui, videos let it crash. The fix I got is that in XBMC I also enable "Zeroconf" and Airplay(mainly anything to with streaming enabled,without passw) ,then I can push any video and it works quite well, as well as photies, but photies won't go to next if you swipe to next photo on phone,however via the mediacentre app it will go to next photo if you swipe on phone. This was only tested on Samsung phones which is S2,Note3,Note2 and S4, S4-Zoom, Galaxy K-Zoom.
Hope it helps