TL;DR – If you have Samsung phone and a Pebble, install a Lineage ROM.
I’ve had my Note 3 (N9005, HLTE) for a few years now. It’s been a decent phone and I’m lithe to replace it as it still has decent specs.
I was pretty late to the Pebble; I got one a few months ago and was thoroughly impressed. The battery lasts for days and it does exactly what I want – alerts for emails, texts, calls. Custom wactchfaces and some simple apps. It’s water resistant, has a larg dev community and also around 1/10th the price of an Apple watch.
Back to the Note. My phone died a horrible death and refused to boot just over a year ago. I was running Cyanogenmod at the time and had successfully updated it plenty of times, but one day it failed to complete and just died. I re-flashed the Stock ROM and sent it Back to Samsung under warranty. After one failed fix they did something and got me a working phone with stock Note 3 ROM. Since then I was a little worried about installing Cyanogen (now Lineage) again, especially as my phone is no longer in warranty. So when I got my Pebble I was running stock ROM Android 5.
The official Pebble app seemed to work OK initially, but kept losing connection. I persevered for a while but it seemed that every time there was a network change the bluetooth link would fail. So every time I lost wifi, or changed from 4g to 3g the watch would lose connection.
I then changed to the open source Gadgetbridge. This has the useful option of reconnecting when the connection drops, but still seemed to frequently drop and not reconnect several times a day, which I wasn’t thrilled with but accepted.
My phone was still stuck on Android 5 and I finally got sick of it and updated to an unofficial Note 3 build of Lineage
This puts me on Adroid 7.12. As it was a fresh start I thought I’d try the official Pebble app again. This time the connection was absolutely solid. Not a single drop in over a week. Result.