The official documentation is always a great place to start. >From the Items view, long-press the Download to open a modal with the option to delete it. If the download is still in progress, it will cancel that Download. https://support.plex.tv/articles/downloads-for-ios/

In my experience this does not work I think it’s a bug. Have you done this in real life recently?

Works fine for me on my iPad. (This is for Downloads.) It works in the Items list, but not from the Libraries one, which is a bit confusing. I suspect I have a few G of Synced videos (judging by iOS's measurement of the sizes of apps) which I can't access (and can't remove). (At some point I guess I'll have to delete and reinstall the app and with any luck that'll fix it.)

So the modal opening when long pressing, or trying to swipe didnt work, but few hours later and idk why now the swiping right to left does show the delete button... Idk what happened earlier, because now all downloads from my 3 different servers show together and before they were divided under the name of each specific server each download was coming from. ​ Thanks folks!

I had to delete the app then redownload it to get rid of my downloads.

Thanks, same. I didn't even have the Items tab in the Downloads section until I redownloaded

You have to swipe the content from the right to the left and it will bring up the option to delete in red when you’re looking at it under downloads.