My wife is an Apple person and I'm trying to help her so she can watch her videos that are stored on a USB stick connected to the router on the TV.
Asus AC86U with an 128GB USB stick (ext2)
old Panasonic plasma TV with Chromecast
I want an app on her iPhone/iPad that can access the videos on USB stick connected to the router and then cast it to the Chromecast connected to the TV with subtitle support. I have tried with VLC on her iPhone, but there's a known bug when the iPhone screen turns off, the streaming stops.
I'm currently trying the same thing for me but on an Galaxy S7, if anyone has some experience there, It seems like VLC can't use subtitles when trying to do this and I've tried LocalCast, but it's quite buggy.