Leanplum automatically captures the push tokens of your existing users who have enabled push permissions, upon the first time they open the app version that is live with the Leanplum SDK. However, you may want to begin sending push notifications to your existing users before they have come back to the app, particularly to re-engage lapsed users or reach users who have yet to upgrade to the latest version.
To handle these use cases, you can upload any pre-existing iOS push tokens or Android GCM registration IDs by utilizing Leanplum’s REST API, specifically the setDeviceAttributes API call.
You’ll need the following data to properly upload users' push tokens:
- Device ID
- iOS Push token or GCM registration ID
Note: It is a requirement to utilize the same format of device ID with the Leanplum SDK and your historical token data. Learn more about which device ID format to use.