You can use Firebase Authentication to sign in a user by sending an SMS message to the user’s phone . The user signs in using a one-time code contained in the SMS message.
Read moreWhy should I use Firebase for authentication?
Firebase Authentication aims to make building secure authentication systems easy, while improving the sign-in and onboarding experience for end users . It provides an end-to-end identity solution, supporting email and password accounts, phone auth, and Google, Twitter, Facebook, and GitHub login, and more.
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