Lillie from Notion here again - this upcoming release is going to seriously help with speed as well as improve usage offline and on unstable connections. This is one of the reasons we've been working on it for so long!
I've tried using Notion on iOS and it feels so slow and I know it is not native because swiping back should get me back to the current page but it just refreshed the whole page. Are there plans migrating iOS to a more native one?