I woke up this morning to an alert on my phone (Motorola Moto E if it matters) that I've already exceeded my 1GB data limit for this month and that has never happened, let alone in the first week of the month. My phone reports the Garmin Connect app as having used ~900MB and my mobile provider reports a long data session beginning at midnight which lasted 7 hours, 46 minutes and consumed 830MB. I was asleep this entire time. I'll now have to disable my mobile data connection and rely on Wifi for the rest of the month to avoid extra charges.
How can I find out what the Garmin Connect app was doing and/or ensure this doesn't happen again in the future?