title: How to save data using Google sign-in
body: <p>I've just implemented Google sign-in into my app using <a href="https://classroom.udacity.com/courses/ud876-5/" rel="nofollow noreferrer">the course on Udacity</a>, <a href="https://developers.google.com/identity/sign-in/android/sign-in" rel="nofollow noreferrer">the developer docs</a>, and <a href="https://github.com/googlesamples/google-services/blob/master/android/signin/app/src/main/java/com/google/samples/quickstart/signin/SignInActivity.java" rel="nofollow noreferrer">a sample on GitHub</a> as resources.</p>
  
  <p>The reason I chose to add sign-in into my app is so that the user could access their data on any devices where they are signed in to that account - i.e. the data would be saved on the cloud, so to speak.</p>
  
  <p>However, I could not really find anything in the developer documentation, or on the Udacity course about how to save data to the cloud using the Google sign-in.</p>
  
  <p>I've looked at the answer to <a href="https://stackoverflow.com/questions/25894531/syncing-app-data-to-google-account">a similar question on Stack Overflow</a> which suggested using the <a href="https://developers.google.com/drive/android/intro" rel="nofollow noreferrer">Google Drive Android API</a> to do this.</p>
  
  <p>I've also had a look at <a href="https://firebase.google.com/docs/database/android/start/" rel="nofollow noreferrer">databases in Firebase</a>, which is completely new to me.</p>
  
  <p>All of this leads me to believe that I need to use my own server to store the user's data (such as Firebase, I think, which is a paid service), or I should use the Google Drive API.</p>
  
  <p><strong>So, my question is, is there a particular API to save data to the cloud using the user's Google sign-in, or would I have to use my own server, or the Google Drive API?</strong></p>
  
  <hr>
  
  <p><strong><em>Edits:</em></strong></p>
  
  <p>To clarify some points made in the comments, I'm assuming Firebase is a paid service from <a href="https://firebase.google.com/pricing/" rel="nofollow noreferrer">it's pricings page</a> if I want over 100 simultaneous database connections (which I don't need now, but soon I may have over 100 users saving data simultaneously).</p>
  
  <p>I am aware Firebase has its own authentication system, but I hadn't considered using Firebase until I realised I need somewhere to save the data, which is why I didn't start using it from the beginning.</p>
  
  <p>I know that Firebase isn't the same as Google Drive, but I was wondering which would be best for my purposes. My app currently reads/writes data to an SQLite database on the device. I want to save this data based on the user's Google account, so that they can sign-in on a different device and have the same data.</p>