How can I rename music videos on my iPhone?
I don't believe it is possible to rename the title of the Music video. The workaround would be this (NOTE: This does involve using a paid Cydia package, Bridge ($1.99)):


Open Cydia and search for "Bridge". Buy it, install it, respring.
Navigate to /var/mobile/Media/iTunes_Control/Music via iFile (or SSH Client of choice)

This is where your music, music videos and movies are stored on iOS.

Tap on the gear icon in the left lower corner, go to File Manager > Search Format and change it to Wildcard if not already selected.
Go back to File Manager and turn on "Song Titles" if not already on. Press Done in the upper right corner.
Swipe up to reveal the search field, select "Hierarchy" and type "*.m4v"

NOTE: If your video files are not M4V, then you would type their extension in it's place eg. *.AVI or *.MP4.
This should search all of the subfolders (F01, F02…) for any video files.

Unfortunately iTunes names them things like "AAWA.mp3", that is why we turned on song titles. It should display the title above the file name for the video.
Once you find the file, note it's location in case you mess up the next step:
Long press over it and choose "Select".
Tap the clipboard in the lower right corner and select copy.
Navigate to /var/mobile/Documents/Downloads and paste the video.
Go to Bridge on the home screen and navigate to /var/mobile/Documents/Downloads
Choose the video file to import, on the info page select "Music Video" and choose a title for it.
Tap import and you should be all set! :-)


It is quite a long and convoluted way to rename a video file, but it is possible (sort of!).