Fire base Vs Cloudkit

Which backend do you all prefer and why? What are the advantages and disadvantages of each compared to the other? I’m trying to decide between the two for an app.

Biggest advantage of CloudKit is the user does not need to log in to use it, “it just works” automatically.
Biggest disadvantage, it’s mainly Apple only. It takes extra work if you wanted a web or Android version

Firebase is made by Google, so it’s biggest advantage is cross platform is way easier.

CloudKit, (depending how you use it) has no limits and you end up just using the user’s cloud storage as opposed to some centralized cloud

Vs Firebase has limits and you have to be careful about reaching them or you could get billed a lot of money

From my experience in working at a company that deals with clients, they mostly prefer Firebase.