title: Amazon Cognito sync how to register the user for developer authenticated identities?
body: <blockquote>
  <p>I am new to amazon cognito sync, my requirement is to sync the user's data across the devices for this i need to implement the Developer Authenticated identities i have used AmazonCognitoUsersPools Demo to signup and sign the users in UserPools.In federated identites i have created a Identity pool and added my user pool id and app id  while creation.From the AWSCognitoSampleDeveloperAuthenticationSample guide i have created a stack and generated Application URL. So now i could able to register the users from browser and syncing their data across devices by using the CognitoSyncDemo, is there any way to register the users from mobile app??</p>
  <p>My Req is to authenticate and sync the users whoom i have registered through CognitoUserPoolsDemo and Sync their data..When i tried these users in cognito sync its not working, Please any one help me out??</p>
  </blockquote>