The leading backend as a service. Amazon’ alternative is AWS amplify.
Realtime app with one line of code with variable config in firebase.
Pricing Is 1 gigabyte of data for free with unlimited users then pay as you go at 18 cents per gigabyte and $0.06 per 100,000 database reads and $0.18 per 100,000 database writes.
Supabase as an open source alternative. Not a 1to1 mapping to firebase. Security rules in sql which is better than firebase. Uses postgres as db. Handles db scaling for you. Pricing for super Bass is 500 MB of data and 10,000 users for free. Supabase is currently based on AWS infrastructure. Currently only has a JavaScript SDK. So it’s missing Android and Apple SDK which I think is really important for mobile game developers.
The reason people use a backend as a service is so they don’t have to self-host their back end.
Fireship firebase alternatives here