What is Firebase?

I don’t understand much about API or back-end and front-end.

Whenever I try to find out what Firebase is, I always get some complicated description involving front-end or something similar.

Is it a no-code/low-code builder?

Is it only a way to configure databases?

Does it have anything to do with web API or Sheets API?

Does it allow you to upload your app to google play store or apple store?

Is it completely free?

Thanks!

I use Firebase to store data in a cloud database, so I can access the data from the apps I develop with AppGyver. It is free as long as you do not use premium features and do not surpass generous read/write quotas.