My partner and I use Google keep as well, and finding a replacement has proven difficult. There doesn’t seem to be an easy drop-in replacement.

• There’s Carnet, but it doesn’t allow multiple people to collaborate on a note and it’s not on iOS.

• There’s Joplin which is way more complicated than it needs to be as a Google keep replacement, and has some limited collaboration options, but no real-time collaboration.

• And there’s etherpad, which is web based, so you don’t need any apps. It has full realtime collaboration support, and “notes” are easy and quick to spin up. The major downsides are a lacking mobile interface and that each person will have to keep track of the various etherpad links.

If anyone has a better solution, I’d love to hear it.

EDIT: I forgot about the Etherpad MyPads plugin which can be used to create a “Google drive”-esque experience with Etherpad. This would be a decent cross between Google keep, Google docs, and Google drive, but it’s still not a perfect keep replacement. An example of this setup can be found here: https://mypads.domainepublic.net/?/login