This app was mentioned in 3 comments, with an average of 1.00 upvote
This can supposedly add captions: https://play.google.com/store/apps/details?id=com.wevideo.mobile.android&hl=en_US.
https://play.google.com/store/apps/details?id=com.wevideo.mobile.android I found this for you, I've not used it personally though. Give it a try.
Very nice plays. If you're on android there's an easy app you can use for your edits, although I didn't think it was bad.
https://play.google.com/store/apps/details?id=com.wevideo.mobile.android