I use Libre 2 with my Android smartphone and I like it. Also, I often use other Bluetooth devices like chest HRM during workouts, smart trainers and others sport machines at the same time. Unfortunately, my HRM conflicts with Libre 2 and I have to choose what to use at the moment: Libre or HRM But sometimes they are both working fine simultaneously.
Moreover, I canāt even connect to my smart trainers at all if my phone is being connected to Libre 2. The days Iām not wearing Libre 2 I can connect to any devices instantly without any struggles. The only one device which is stable working with Libre 2 simultaneously is BT headphones which I use during my walks. Iām exhausted of that and Iām angry! Argh!!! So, each time I spend a lot of time to get all things going instead of just start training.
Guys, any ideas what that problem is? Is somebody else experiencing such problem?
I donāt use it, but has it always done this or is this a relative new issue? You might try:
Uninstall the Libre App and reinstall. I read doing this might kill your current sensor session so you might want to wait until the end of a sensor session before doing this.
Not sure how Libre works, but for dexcom each new transmitter is listed as a new bluetooth device, so I always go into bluetooth settings and clean up old transmitters that are not being used.
It is not a new issue, this problem is actual for each sensor I apply. You are right that reinstallation of Libre App kills current sensor session. It seems the problem is somewhere deeper. Maybe BT version (4.2) is too old and it cannot treat simultaneous connections properly
There was a lot of stuff about this two or three years ago with respect to the Dexcom CGMs dropping out. There was no conclusion but it seemed to be associated with noisy environments; maybe specific phones were more prone to the problem, but most experiences seemed to involve some kind of disconnection associated with place and/or sensor (transmitter) obstruction. Microwaves were suspected, but then they always are
There are some known and easy to demonstrate problems:
Our bodies block bluetooth. If your body is between your phone and your sensor the communication relies on signals bouncing off walls. If you are in a large space (a big gym, a forest) that doesnāt happen; no communication.
At least with the G6 the sensor (transmitter) only transmits once every 5 minutes. If that transmission misses there is (so far as I know) no recovery; the data will be absent until the next 5 minutes. In noisy environment the sensor has to compete with all the other things that are transmitting pretty much all the time, readings get dropped.
The G6 (I donāt know about the Libre2) uses bluetooth LE (āBLEā), that requires an up-to-date bluetooth implementation - the support needs to explicitly include BLE and, more important, it needs to work. Itās possible your phoneos has a problem (hum, this one isnāt easy to demonstrateā¦)
The easy first step is to try to use your HRM and the Libre at the same time in a clean environment; take a hike up into the hills, sit down with both sensor and HRM in clear line of site of the phone (no intervening bodies etc.) If they work fine then it isnāt the HRM - it may be a part of the problem, perhaps it spams the airwaves continuously (worse than your headphones), but itās not the whole problem.
But sometimes they are both working fine simultaneously. 
