I can't get onto my YouTube inbox?

On my iPhone I have the YouTube app but there is no option to get onto my inbox anymore so I use the Internet to see it. I go onto the mobile version of YouTube but I recently changed it back to desktop to view something and now I won't let me change it back to mobile version. I have read that YouTube is doing this so that everyone downloads the app but it's very annoying. Also if anyone knows how to actually get onto my inbox via the app then let me know. Thanks.