Youtube stupidity+Android Phone

So I have an established youtube account, it used to be just youtube.com/myusername as my “account”, then because no one wants to use crappy Google+, I’m forced to use my gmail acct as my “main” one which has NO subscriptions or uploaded videos, then go to “switch account” to my old channel/acct on a desktop PC. Which sucks, but no problem.

Anywho, I now have an android phone, and I can only sign in with my gmail account on the youtube app, and as far as I can see there is no “switch account” option so I have none of my hundreds of subscriptions, crappy recommendations, etc etc. I can sign out and sign into a different account, but my youtube.com/username account does not have a gmail address as far as I know.

Is there a way to switch accounts? It’s a Galaxy S2.

Thanks!