Google Sign-in is a free service . To use Google sign-in you have to use Google’s Firebase authentication service. Pricing for Firebase has three tiers, you can see the pricing at this link https://firebase.google.com/pricing/.
Read moreHow do I add Google sign to my website?
Integrating Google Sign-In into your web app
Read moreHow do I use Google Firebase?
Getting started with Firebase
Read moreHow do I sign into Google firebase?
Enable Google Sign-In in the Firebase console:
Read moreHow do I use Google firebase in flutter?
Android setup
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