I use MiniKeePass (https://github.com/MiniKeePass/MiniKeePass) on iOS and keepassx2 on Linux. Works fine.
The new fork is intriguing. Need to take a closer look.
I upload my keepass and key file to Dropbox (I know, I know) and then export them to MiniKeePass from the Dropbox app. MiniKeepass auto-associates the key file with the kdbx if it has the same filename as the kdbx, but with a .key extension. I can even edit the DB with Minikeepass and upload it back to Dropbox. It's not as sexy as an Android setup, but it works quite well for me.