I just started using it last week so there may very well be other things I may not be aware of, the app is kind of garbage but here’s some things I found out about to make it easier. Firstly in the accessibility settings there’s an option to display some additional buttons if VoiceOver is on, you obviously want that turned on which it already started out being for me. That adds a bunch of buttons running down the right middle of the screen to like, follow, read comments and so on, as well as previous and next buttons at the top as an alternative to manual scrolling. By far the biggest annoyance to be aware of is that for some reason with VoiceOver on when you touch some parts of the screen or do some actions that cause a screen change like following someone or opening the sharing screen, it’ll scroll you back to the top of your feed unless you’re holding your finger down to prevent the focus from moving. This is why so many people prefer to scroll with VoiceOver on, which isn’t as bad as it sounds because the video takes up nearly the whole screen. With VO off, single tapping the video pauses, while double-tapping likes it which is accompanied by a haptic. Then if you want to do anything else you turn on VO then immediately start touching the screen where the buttons are so it doesn’t scroll you to the top. For the website, which in some ways is better, there are 2 decent ways to browse the feed. One is just going by graphic which will automatically play the video and the buttons to like and so on will be immediately below, or an even better way is to open the comments view from any video, find the dialog that pops up and then scroll with either down/up or the next and previous buttons. The advantage to doing it this way is you can also rewind and fast forward the video with right/left arrows and you have immediate access to comments.

Hope this helps. I got a lot of this from @talon who’s been using it for a lot longer than me.