I'm looking for a way to schedule notifications set by the user, which will notify all the devices they are using my app on.
Currently I'm using firestore to store the users data, including when the notification is due, and AlarmManager to set the alarms. The problem with this is that the user can set the notification on one device, but it's not synced to their other devices.
My plan is to use scheduled cloud functions, and then cloud messaging to notify the user on all devices. However I can't seem to find a way to update or cancel the cloud functions. Users could have multiple notifications set at one time.
How could I go about doing this, or is there a better way?