For the past couple of weeks I've been fightng with my iPhone 7 (running iOS 11.2.5) suffering from extremely low WiFi download speed. By a total accident I've realized that if I kill GC app, the network speed magically returns to normal 70-80 mbps. When I re-open GC it instantly drops to 1-2 mbps tops.
I've confirmed this with my another iPhone 7 (business) and my wife's iPhone 6 (both on iOS 11) - the network speed gets crippled as soon as the GC app is opened. This has been confirmed with 4 different WiFi networks I had access to. Hence I believe it's the app bug/issue, not just an isolated case, specific for me only.
Has anyone observed the same / similar symptoms? Are Garmin engineers aware of this? Given my network speed issues history, I'm willing to assume they were coming and going simultaneously with GC updates...