It would be good if we had visibility in the state of the sync session, particularly around understand how many change sets are still on the local device and awaiting upload.

The use case is to easily (and accurately) report to a user that their local changes haven't yet been synced with other devices.

Ideally it would come in two flavours, one API to retrieve the current change set count, then support for a listener which would trigger when the number of pending change sets increases or decreases.