I'm working on a project that lets users track vehicles from their phones, each of theses vehicles have a device (running android) that sends the gps location and all the required info to a realtime database and then the user that requests to see a vehicle's location gets those info from the mentioned database, what database is best to work with, I'm looking for something that's open source, free and easy to use since I'm fairly new to this 🙂.
I would recommend Firebase for this as it has an amazing SDK with pretty much everything you need out of the box. Depending of how 'realtime' your project needs to be, you can go with Firestore, latency is a bit higher than Realtime DB, but price is much lower. The combination with Node, using CloudFunction, will streamline your process having it all under the same roof.