A really nice summary. Very useful. Thanks!

It has swipe up/down + double tap gestures. You can also customise the home and back buttons.

It has swipe typing plus a lot of other new features/theme customisation that openboard didn’t have.

If you like Tree Style Tabs I’d also recommend trying Sideberry. Does the same thing but has some additional functionality.

PhotoDemon is close to what you’re asking for. It has the basic functionality the average user needs yet is still lightweight and fast to start.

They have different usage scenarios.

LocalSend is for the occasional sending of files/folders from A to B or B to A (One direction only).

Syncthing’s primary usage is for keeping the exact same copies of files on A and B automatically.