Bangle2 bluetooth range

Posted on
  • I was wondering what is the supposed average range for bluetooth with the bangle2.
    I noticed Gadgetbridge on my phone loses the bangle connection if my wrist goes farer than 30cm of my phone. A luck i wear it on my left wrist and my phone is often in my jeans left pocket.
    I could do with that, but i ve recently read that bangle2 was supposed to have a wide large range, bigger than bangle1’s. And when i wear the bangle one, my phone can be at the opposite of the room or even downstairs, and gadgetbridge still considers they are connected.
    Any idea/clue/information about this ?

  • I've got the exact opposite experience. My Bangle.js 1 won't stay connected unless I keep my phone on me, while the Bangle.js 2 will stay connected two rooms away (AAC walls). The Bangle.js 2 should definitely have better range than what you're seeing...

    Are you on the latest firmware?

  • In my appartment it is approx. 10m. But this depends also on the quality of the antenna in the phone. There can be a huge difference between models. If you never encountered problems with your phone's BT before this is strange.

  • The range on Bangle.js 2 is usually pretty good - much better than a Bangle.js 1.

    I'm pretty surprised about that - what signal strength do you see reported when it's nearby and you are pairing? Lots of aerials, or not many?

  • with no walls nor objects between the watch (100% charge)and my phone (and no other bluetooth device around)
    at 50 cm : -78 db (if worn) -68 db (if laying on the wooden desk)
    ar 45 cm : -68 db
    at 20 cm : -62 dd
    put against the phone : -42 db

  • Not sure if it is related to the new update of Gadgetbridge (on Android), but since a few days, the range has drastically reduced and I sometimes cannot (re)connect the Bangle2 at all...

    That said, i retested with the Bangle1 and it is still connecting without any issue even at a large distance

  • Did you try connecting from Gadgetbridge without enabling Pairing?

    -78 db actually sounds about right to me

  • i don’t pair. I always directly connect directly from GB.
    I think i read somewhere that GB had difficulties to connect if the watch was already paired with the phone. But i may be wrong. Do you think i should pair before at least just to see the difference ?
    -78 sounds not that bad indeed, but the GB icon switches to disconnected at this distance and if i put them back closer to each other it says it is actually trying to reconnect and fails most of time now..
    What i don’t get too is that, meantime, GB can connect and sees the Bangle-one which is off and in its box, downstairs, in a house with thick walls.
    I ll try to delete the pairing of the bangle2 in GB and restart the procedure of pairing it, and i ll see if there s a difference.

  • Sorry to bring this up again, but I can't find a reason why my BangleJS2 loses all Bluetooth connection with my phone beyond 50cm.

    At first I thought it was related to GadgetBridge only. But I don't have this problem with the BangleJS1 which stays connected with GadgetBridge even beyond 10 meters, and yet the BangleJS2 doesn't lose the connection at less than 5 meters when I'm connected with the WebBLE or nRFToolbox, from the same phone or from another device.

    The problem seems to be only between the Bangle2 and GadgetBridge (which are both up to date with the latest versions).

    Is anyone reporting the same experience? Or would have any idea what I am doing wrong? Could it be that the way the Bangle1 and Bangle2 connect to GadgetBridge is different? Aren't the protocols or dialogs supposed to be the same?
    Won't the multiple attempts to reconnect to GadgetBridge (often unsuccessful) drain the battery (in addition to the synchronization errors it already causes: time, step counter...)?

    Thanks in advance for any light brought to this obscure mystery

  • I haven't heard of any issues with this before... I know it's a hard one to test, but does the issue seem to be unique to that phone?

    Could it be that the way the Bangle1 and Bangle2 connect to GadgetBridge is different? Aren't the protocols or dialogs supposed to be the same?

    Well, generally they are, but the Bangle.js 2 does use a newer version of the Bluetooth stack (Nordic SDK15 vs SDK12) that supports Bluetooth 5 - so I guess it could be some issue related to that.

    Bluetooth 5 does enable some other features (longer range, higher bandwidth) and I guess if there were some incompatibilities that could cause issues.

    But are you sure it's not related to power saving on your phone? Android tends to apply power saving to apps by default unless you turn it off, and it's entirely possible your phone has some rule in there like "if an app's connected to a bluetooth device and signal strength is low, close the app" as I think the heuristics for it are more or less manufacturer dependent.

  • Hello Gordon, and thanks for taking the time to look at my slight problem.

    Indeed the powersaving of the phone could have been the reason why it loses connection with the Bangle. But I checked again and GadgetBridge is indeed in the list of exclusions. And as mentioned, the case does not occur with the Bangle1.

    But this nuance of Bluetooth version between the two Bangles could indeed be at stake, I'll dig on this side in the specs of my phone. It is not a very recent one and with a special OS, so it could indeed be a bug with the Bluetooth version 5

    Thanks again, and I'll come back here with more information, if I find any

  • Back with specs dug up
    My phone actually fully support Bluetooth5.00 (Bluetooth® v5.0 (LE up to 2Mbps), ANT+)
    Still looking for a clue (and still confused)...

  • Hello @Gordon

    I come back again on the problem I have of limited distance of bluetooth connection from my Bangle2 (yes, again, sorry)

    First of all, after several tests I realized that my first analysis a few months ago was wrong, because I did not wait long enough.

    I did some more tests, with several different devices (a GSM galaxy S9 under /e/os, an iPadpro 10.5 under iOs13, a MacPro under OsX.13) and different applications (nrfToolBox, WebIDE, Chromium, LightBlue and obviously GadgetBridge)
    With all these different configurations, beyond one meter (on average) after about ten seconds, with or without movement, the Bluetooth connection is lost.

    There is no such problem with any of the other bluetooth devices tested in the same configuration, including the Bangle1.

    Until now, this was not a major concern, my phone being always in my pocket, my wrist never really very far. But when I want to be able to use the Bangle2, and the CSC application with my bike for example, it can't work, the distance being a little more than a meter.

    Is there any other test you would advise me to do, or a magic code maybe that would make this range more important?

    In any case, thank you again for this little marvel that I cherish every day, and for the implication you invest in it, it's really a very nice project !

  • Hi - this does change things a bit if you're finding that it fails with multiple different devices. It would seem that the signal strength is ok, so I guess it could be an intermittent connection. I guess the only solution really is to look at a replacement.

    Out of interest, is it more likely to drop out if you move it quickly or tap the watch body? It could be an intermittent connection.

  • Thank you @Gordon

    I guess the only solution really is to look at a replacement

    Ok, sorry about that, I wish it was something that could be solved more simply, maybe with code, but anyway, if you think the watch needs to be replaced...

    is it more likely to drop out if you move it quickly or tap the watch body?

    The disconnection just happens with the gradual removal, even slowly

  • Sorry for the delay - somehow I missed your reply.

    Not sure why I didn't think of this before, but please can you install the 'cutting edge' firmware, use the 'Custom Boot Code' app (, enter NRF.setTxPower(8), upload, and see if that helps?

    The default is 0 dBm, so going up to 8 should give you a real boost. Previous firmware versions for Bangle.js 2 weren't setting the transmit power for connections properly so it wouldn't have had a huge effect

  • Hello @Gordon
    No worries about the delay, I'm naturally patient and I know you're very busy.
    And being patient is worth it because you found a solution to this little problem :)
    I installed the latest CuttingEdgeFirmware
    And copied/pasted the code provided in the CustomBootCode app.
    Unfortunately, the "upload" button seems to have no effect (on my iPad with WebBle). as if the code had a typo (I tested with another code)
    Maybe I can go through the IDE?

  • Ahh - sorry - try putting a semi-colon on the end of the line: NRF.setTxPower(8);

  • Thank you ! and it looks like it is working : I ve just done a few tests and connection between Bangle and phone still working at 5meters ! (enough for my use with my bike)
    Again, thanks a lot

  • Post a reply
    • Bold
    • Italics
    • Link
    • Image
    • List
    • Quote
    • code
    • Preview

Bangle2 bluetooth range

Posted by Avatar for nicoboss @nicoboss