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Compromising Garmin Sport Watches: A Deep Dive into GarminOS and Its MonkeyC VM

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31–40 of 77 posts

Re: Compromising Garmin Sport Watches: A Deep Dive into GarminOS and Its MonkeyC VM

#31
post #10

Earlier quoted context omitted.

Garmin watches work well with the desktop sports tracking program MyTourBook. I've never had to activate a Garmin watch or register it online in order to use it. Not connecting it to Garmin Services and apps may limit access to 3rd party apps, or at least make it harder to load them load though. (I haven't researched side loading since base features are fine for me). MyTourBook supports FIT/GPX/TCX/etc, has maps, cal…

> This is with syncing over USB btw. Nevermind it is not worth the trouble, vs handing in anonymized data with a temp email

Right, anonymized data that shares your vitals 24/7 (which are fairly unique) and location data which totally cannot infer your home and work locations. You’re deluded if you believe this can truly be anonymized and stay anonymized.

Re: Compromising Garmin Sport Watches: A Deep Dive into GarminOS and Its MonkeyC VM

#32
post #6

Earlier quoted context omitted.

I am pretty sure you can use the sports tracking functions in garmin without an account, if not, at least without connecting the watch to a phone. You just need to connect with usb to copy the activity file (.fit) which can be converted to tsv. regarding the passive tracking I dont have a clue

Really? I recently got a forerunner 265 and it definitely didn’t give the impression that was possible. The battery life is also nowhere near the advertised length (13 days). Most disappointing is that their support people say to expect about 60% of that, which is what I’m getting. That said, this will likely be the replacement for my Pebble. Battery life over 6 days, buttons to control music playback, and an English…

My 2S uses up 10–11% per 24h in watch mode (using the gps uses more battery). But I had to disable the O2 measurement altogether because that chewed through the battery and isn’t that useful to me.

Re: Compromising Garmin Sport Watches: A Deep Dive into GarminOS and Its MonkeyC VM

#33
post #6

Earlier quoted context omitted.

I am pretty sure you can use the sports tracking functions in garmin without an account, if not, at least without connecting the watch to a phone. You just need to connect with usb to copy the activity file (.fit) which can be converted to tsv. regarding the passive tracking I dont have a clue

The main thing that I miss from connecting to Garmin Connect is downloading the EPO/CPE files which speedup acquiring the GPS data a lot. see https://support.garmin.com/en-US/?faq=6IbaJEHc1i9gydzQomXzyA To avoid waiting up to several minutes to get the GPS data when I start my workout, I'll switch to an exercise mode to start acquiring the GPS data while I change into my workout gear and leave the watch near a window…

I think you can download the EPO file manually.

https://github.com/StevenMaude/armstrong

https://github.com/StevenMaude/epo-bin

Re: Compromising Garmin Sport Watches: A Deep Dive into GarminOS and Its MonkeyC VM

#34
MonkeyC is such a funky language to write. It's obviously modeled on top of java, just with some syntactic differences making it instead look like a mashup with javascript.

I get why they made their own high level language to some extent, instead of shoehorning in something else. But making your whole stack from scratch must lead to lots of holes like these.

But a very nice blog post. Learned loads more about what's going on under the hood, very interesting.

Weird how permissions is mainly a UI thing. Aka how they're used is that if you have them you can use them, and it's mainly a UI thing to just show the same list in the app store. So not really enforced. I guess the fix then is to make sure it's not possible to lie in the app store?

Re: Compromising Garmin Sport Watches: A Deep Dive into GarminOS and Its MonkeyC VM

#35
post #27
post #25

Earlier quoted context omitted.

Most current Garmin watches have 7+ days of battery life depending on how much you use the GPS.

I would prefer wearing a lightweight band overnight. I wish Garmin still made the Vivo* models

I wear a Forerunner 735xt, time for anecdata!

It may be bigger than a band but it's surprisingly small and very light to the feel, I barely notice the difference with the Fitbit Charge HR 2 I owned before. Major reason why I'm not upgrading to a Fenix of something like that.

Plus up to 15 days on battery when not using GPS, much more if I disable continuous HR.

Re: Compromising Garmin Sport Watches: A Deep Dive into GarminOS and Its MonkeyC VM

#37
post #27
post #25

Earlier quoted context omitted.

Most current Garmin watches have 7+ days of battery life depending on how much you use the GPS.

I would prefer wearing a lightweight band overnight. I wish Garmin still made the Vivo* models

Personal preference but I find the Venu so light that it does not bother me for sleep the way my Fossil Explorist did (which also never had enough battery to do overnight tracking!)

Re: Compromising Garmin Sport Watches: A Deep Dive into GarminOS and Its MonkeyC VM

#39
post #6

Earlier quoted context omitted.

I am pretty sure you can use the sports tracking functions in garmin without an account, if not, at least without connecting the watch to a phone. You just need to connect with usb to copy the activity file (.fit) which can be converted to tsv. regarding the passive tracking I dont have a clue

Really? I recently got a forerunner 265 and it definitely didn’t give the impression that was possible. The battery life is also nowhere near the advertised length (13 days). Most disappointing is that their support people say to expect about 60% of that, which is what I’m getting. That said, this will likely be the replacement for my Pebble. Battery life over 6 days, buttons to control music playback, and an English…

The SpO2 sensor uses significant battery life. This is why is princely only enabled during workouts and sleep, but it can be set to run nonstop or not at all. Double check that setting.

My 945 is pretty close to advertised when I’m not too active.

Re: Compromising Garmin Sport Watches: A Deep Dive into GarminOS and Its MonkeyC VM

#40

Anyone got a recommendation for fitness wearables where you can opt out of having to sign up with an account, and can export data out of it in open/standard formats?

I haven't tried one as I am currently happy with my Garmin vívoactive 3, but the BangleJS 2 looks very interesting: https://banglejs.com/
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