Currently, when exporting contacts from the Contacts app, the UI allows you to select multiple contacts to be exported to the SIM card. During this process, only one contact is updated at a time via updateContact: https://github.com/mozilla-b2g/gaia/blob/master/apps/communications/contacts/js/export/sim.js#L138 I was curious what was the thought process behind doing the export this way rather than sending all contacts down in one call? There could be added benefit to knowing how many total contacts would be updated at the very beginning of the export (or knowing when a call to updateContact would be the last one).
[Blocking Requested - why for this release]:
Comms triage: Performance improvement. Let's backlog it.