Connect draining iOS battery

a5bc35bf73fc459080d59d24971dce04 Thank you for sharing what worked for you. 

5208868 bluefish 5555277 Can you all try this to see if that resolves anything. If it does not we will reach out to you via email to gather some information. **

Spent way too long thinking I was the only one with this, and it was driving me nuts, so I plugged my iPhone into a PC and actually traced what's happening over. Posting it because I'm pretty sure it's a real bug and I'd love someone at Garmin to look.

Short version: while the watch is connected, Garmin Connect keeps a constant BLE stream running — about 2 to 4 GATT indications every second, 24/7, even when the watch is just sitting there with nothing to sync. That constant chatter makes iOS's bluetoothd hold a "prevent sleep" assertion almost nonstop, so the phone never actually deep-sleeps.

From a sysdiagnose:

- bluetoothd held the system anti-sleep assertion for 34.7h out of 57h logged (61% of the time) — by far the biggest offender.

- Overnight, screen off and unplugged, the phone lost 5-8% per hour. A healthy iPhone loses under 1%/h in standby. So roughly half the battery, every night.

- The BT radio itself barely uses any power. The damage is that keeping the phone awake keeps the CPU, modem and RAM running all night. That's also why the Battery screen shows nothing useful: iOS files it under "System", so you never see Garmin as the cause.

Disconnect the watch and the stream instantly drops to zero and the phone sleeps fine. Reconnect and it's right back. Fully reproducible.

Stuff I tried that changed nothing: Background App Refresh off, notifications off, Location = Never, no Connect IQ apps, latest firmware, reinstalling Connect, unpair/re-pair, force-quitting the app (state restoration keeps the session alive anyway), even a full iOS network-settings reset. The only thing that stops it is turning Bluetooth off — so right now there's no way to stay connected without bleeding battery.

Setup: iPhone 15 Pro / iOS 26.5.2, Vivoactive 5 (firmware 17.05), Garmin Connect 5.26.2.

Can someone at Garmin please look into this? As far as I can tell the fix is to stop the watch/app from streaming constantly when idle and let the link go quiet between syncs. I've got the full sysdiagnose, raw logs and the power-log data; happy to send whatever helps you reproduce it.