How to make watch-face app and other processing app communicate? (on bluetooth paired smartwatch).

edited May 2017 in Android Mode

I'm not even close to app developer

but with the help of android mode and using simple udp libraries and controlp5 library,

I was able to connect the app to the self made IOT objects and control them!


In the pre-release version for android mode, I found something called watch face,

I tried using it, and luckily my sketch showed up in the smart watch!


I tried uploading the same code (basically clickable button to send data via udp communication)

but of course it didn't work.

(watch face app data seems to be self contained inside the watch.)


If i give permission to the app in smartphone,

It is possible to make sketch get inputs from or give outputs to other.


still, I can't figure out how to send data from watchface app or make watchface app react on other inputs.

since the watch is paired to the smartphone via bluetooth,

if there's a way to let "smartwatch (watchface app) - smartphone (android mode app)"

to communicate with each other, I think it will do the work.

(or perhaps a way to allow watchface app to burrow smartphone's wifi resource? )


Any similar attempts or comments are welcomed

thank you.

sorry for the bad english,

(not native speaker...)


  • edited May 2017

    it seems bit long.

    the main issue was "are there any way to make watchface app to be connected to the outside?"

    ex.) I can make a button to make the watch screen turn white and black

    but I can't find a way to use that button to turn on the LED connected to arduino

  • edited May 2017

    I've been working on

    connecting watch-face sketch with android app sketch

    using ketaibluetooth tutorials, but it keeps on failing on the watch-face side.

    I've been adding fragments of bluetooth codes on the watch face side

    and it seems like

    import ketai.ui.*;

    importing those resource on the sketch is okay.

    KetaiBluetooth bt;
    bt = new KetaiBluetooth(this);

    initiating it is okay.


    but using it is not okay.

    perhaps it's something that I can't just do in the current version of processing for watch-face

  • Answer ✓

    I don't have any experience with the watchface myself and I do not have one to try stuff on. I would think it is possible to create a bluetooth connection if watchface follows the same layout of any Android device. If i were you, I would dig under the hood of those libraries and I would get familiar with the watchface and ketai bluetooth source code. This will give you an insight of how things work for each application and will give you confidence to implement or create further changes for your application.

    I would like to add that I was trying to run a test last night using thecamera ketai library and I am not sure it is working at the moment. I can do more testing later today and let you know if ketai is working. You can do the test yourself as well. Just open the ketai examples and run in on your device (use a phone, not a watchface).

    One more thing. How familiar are you with bluetooth apps? I suggest you work in setting up a local bluetooth between two devices (if possible) before you get to work in the watchface. Getting familiar with proper function calls and having a testing unit on the side will always help in debugging and maintenance portions of your project.

    As a final note, if you become familiar with the watchface source code, any B2 code available for watchfaces in the web can be used in the processing side after some proper tweaking.


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