I'm biased since I work on it, but https://ditto.live/ https://ditto.live/ provides an SDK that allows P2P and cloud sync. You interact with it like a database:

I'm biased since I work on it, but https://ditto.live/ https://ditto.live/ provides an SDK that allows P2P and cloud sync. You interact with it like a database: write your queries against your data, and it will move between devices automatically