[HN Gopher] How to Build a Smartwatch: Picking a Chip
___________________________________________________________________
How to Build a Smartwatch: Picking a Chip
Author : rcarmo
Score : 215 points
Date : 2025-05-14 07:02 UTC (15 hours ago)
(HTM) web link (ericmigi.com)
(TXT) w3m dump (ericmigi.com)
| mrheosuper wrote:
| Interesting they did not go with 2-chip design(1 for main
| application, 1 for BLE stuff). Which is sometime makes sense
| because high power mcu usually does not have RF
| mschuster91 wrote:
| the more chips you have, the more complex the project becomes.
| BOM is one thing, every chip needs support passives and
| oscillators, but now you also need to coordinate communication
| between the chips, you need to devise a way to update firmwares
| and access both chips for debugging purposes... that might be
| worth to trade off for less battery life.
| mrheosuper wrote:
| in my experience they are not that much difference between 2
| design. The BLE FW is a binary blob that you will download at
| boot with 2 chip-design, or load it to correct address with
| single chip-design.
|
| From the CPU perspective, they are the same
| Max-q wrote:
| From a PCB layout and supply chain perspective, it's a big
| difference.
| mschuster91 wrote:
| > in my experience they are not that much difference
| between 2 design.
|
| Depends!
|
| If the two chips use UART or SPI for intercommunication,
| okay, you need two lines between the CPU and two GPIO lines
| for wakeup, and JTAG can be shared anyway.
|
| But if you use stuff like shared memory, or want to do
| stuff like updating the display not just from the high-
| power chip but also from the low-power one, suddenly design
| becomes much more complex.
| bArray wrote:
| The "high-end" modern MCUs are pretty great, you have the NRF
| offerings, but also the likes of the ESP32 where you can get
| Bluetooth and WiFi in a single package.
|
| Personally these days I would lean towards the ESP32, they
| continue to iterate on it nicely and it has great community
| support. I'm personally developing a smart watch platform based
| on micropython.
| jsheard wrote:
| Aren't ESP32s way more power hungry than typical BT-only
| parts though?
| bArray wrote:
| Not insanely for a smart watch. Your smart watch battery
| will be something like 200mAh, so for 20 hours you need to
| average 10mAh. With zero optimisation, screen refresh rate
| at 30+fps, I have smart watch chewing 30mAh.
|
| Getting down to 10mAh is not so bad. If you're not actively
| driving the display, you can under-clock significantly [1],
| if you're not using WiFi you can turn the modem off [2].
|
| [1] https://docs.espressif.com/projects/esp-
| idf/en/stable/esp32/...
|
| [2] https://docs.espressif.com/projects/esp-
| idf/en/stable/esp32/...
| mrheosuper wrote:
| no, esp32(the original one) is insanely power hungry,
| especially its radio.
|
| Also 20 hours of runtime is horrible.
| bArray wrote:
| I'm getting 10 hours run time with the screen
| continuously running and drawing graphics every refresh
| in micropython - extending this time out is definitely
| possible.
|
| There are many ESP32 variants, depending on what you pick
| some may be more compelling for your use-case.
| mrheosuper wrote:
| Well, we are talking about smartwatch use case.
|
| Even some newer variant like S3 or C6 only has acceptable
| power consumption, if what you are after is run-time they
| are not the best fit.
| jononor wrote:
| It might be just-about acceptable for a smartwatch. But
| anything the micro takes out of the power budget means
| less screen and radio time, which does add constraints.
|
| PineTime, based on NRF52, will get you 4-7 days of
| practical usage.
| aa-jv wrote:
| Can confirm, I regularly get about 9 days of charge on my
| PineTime, running the latest PineTimeOS release. Its
| gotten better and better over the years, and the
| functionality keeps coming ..
| bArray wrote:
| I used to use the PineTime with PineTimeOS, but mine
| eventually broke (corroded inside), but not having WiFi
| made it annoying to develop for. With WiFi suddenly you
| don't need to communicate regularly with a phone and the
| possibilities really open up.
| MomsAVoxell wrote:
| I get that kind of experience with the Watchy... but the
| problem is, its quite a bulky device and gets a bit
| tiring to wear after a while.
| bayesianbot wrote:
| There are ESP32 watches. One I have[1] comes with quite
| thick 940mAh battery but my understanding is the battery
| life still isn't that amazing (just got it, haven't
| really tested the battery) - something like less than a
| day of constant runtime or few days if you turn it off
| constantly
|
| [1] https://lilygo.cc/products/t-watch-s3-plus
| bArray wrote:
| I have a similar one with a microphone, I dread to think
| how the GPS module and LoRa of that variant affects
| battery life!
| jononor wrote:
| Yeah I got one of those as well. An the older non-S3
| version. Fun for developing, very powerful. I use it for
| developing ML applications for watches etc (emlearn
| project). Great device for that, but battery life is not
| its strong point.
| the__alchemist wrote:
| Does this apply to C-3 and C-5 as well?
| mrheosuper wrote:
| I would not consider ESP32 high-end MCU, it still lacks many
| peripheral(DSP, GPU), its core clock is not high(only 240mhz
| iirc).
|
| Recently they release ESP32P4, with very strong performance,
| but like you guess, without Radio
| bArray wrote:
| We are talking about an MCU, not a CPU :)
|
| I think once we start talking about GPU, MMU, USB, display,
| etc, we're getting towards a CPU of sorts.
|
| Speaking of a low-end CPU, I want to test out the RV1103
| Rockchip, those crazy little chips are running Linux
| apparently [1], and even able to run Python [2]. Depending
| on power draw, a Linux-based smart watch could be on the
| horizon.
|
| [1] https://www.luckfox.com/EN-Luckfox-Pico
|
| [2] https://wiki.luckfox.com/Luckfox-Pico/Luckfox-Pico-SDK
| bobmcnamara wrote:
| ESP32-S3 has all that minus a GPU. Runs Linux.
| bArray wrote:
| Looking at that now [1], seems like something I need to
| run a test with!
|
| [1]
| http://wiki.osll.ru/doku.php/etc:users:jcmvbkbc:linux-
| xtensa...
| the__alchemist wrote:
| USB is trivial for most modern MCUs; even low-
| power/minimal-cost ones.
| mrheosuper wrote:
| Yes, we are talking MCU, it's very common now that mcu
| has gpu now.
|
| For ex: Bes2700bp and bes2800 has 3d GPU iirc. Their spec
| is very impressive, too bad that their SDK is kind of
| limited to non-Chinese vendor
| Max-q wrote:
| While the ESP32 is great for many applications, it's not for
| battery operated stuff. When an nRF draws 1-2 mA when using
| BLE, ESP32 will draw 40 mA. And the chip they selected is
| even more efficient.
|
| The low power chips can also run in low power mode without
| BLE running using micro amps, something the ESP can't match.
|
| I really like ESP32 and I hope they have a low power chip on
| their roadmap.
| bArray wrote:
| Sure I agree, but the WiFi functionality is a killer
| feature. As mentioned in another comment, it means a smart
| watch stops being a smart phone addition and can actually
| operate as a stand-alone device.
|
| Years ago I had a "smart" watch that had a sim card and was
| a full mobile phone within its own right, I think it was
| just 10 years or so too early.
| the__alchemist wrote:
| Concur. With nRF, you have to bolt on a separate 70002
| Wi-Fi Chip.
|
| And this chip isn't a normal QSPI chip where you read the
| datasheet. You _have_ to use NRF connect, and Zephyr.
|
| So, this brings up the obvious question: What if I don't
| want my whole firmware to be Zephyr nRF-connect, just for
| a Wi-Fi chip?
| bArray wrote:
| Manufacturer lock-in can be quite a problem. I'm not
| saying the ESP32 solves this fully, but you can mix and
| match as you like, and it's highly encouraged. I think
| with the ESP32 most build upon Free RTOS but I'm not
| aware of a strict requirement.
| the__alchemist wrote:
| Of note, you can just pull in a lib to use Wi-Fi and BLE
| on an ESP32 (C-3 at least). I've done it. It doesn't
| imply any changes to your firmware architecture. That's
| the part that bothers me about Nordic's approach.
| numpad0 wrote:
| It's just a watch. You don't need a full UNIX computer to tell
| time, or to record heart rates or pinging AWS for those
| matters.
| znpy wrote:
| Interesting comment, because according to
| https://en.wikipedia.org/wiki/PDP-7 the PDP7 (the first
| computer "UNIX" ran on) had ~9.2KB of memory (supporting up
| to 144KB).
|
| Most contemporary SoCs will have more memory (and compute
| power) than that.
| internetter wrote:
| That's a complete non sequitur. Just because UNIX can run
| on lower end hardware doesn't mean "a full UNIX computer"
| is the best tool for the job.
| ItsHarper wrote:
| The Cortex-M33 core in the SiFli chip will be much faster than
| the M4 cores that the fastest released Pebble watches used, so
| a faster MCU than this is not something that's needed. However,
| more battery life is very welcome, and the fact that they're
| using MCUs with integrated Bluetooth this time seems to be a
| huge part of the upgrade from about a week of battery life to
| about a month of battery life.
| alin23 wrote:
| Glad to finaly see someone in the low-power chip industry going
| in the open source direction. Thanks for the insight!
|
| When I saw rePebble be announced, I signed up for it right away.
| Only later I realized I actually don't want a smartwatch, I want
| a dumb watch with vibration notifications.
|
| I know I'm in the minority, but it's a niche that has a few very
| interested people in it [0] [1] [2]
|
| After wearing the Casio F105 for the past 2 years, I can't go
| back to something larger, heavier or thicker than this. I could
| accept weekly battery charging for the benefit of having some
| bluetooth functionality.
|
| So nowadays I'm looking for a super small bluetooth chip that can
| power a small vibration motor, which can receive all
| notifications from my iPhone. I would like to glue that chip,
| motor and a small lithium battery between the two straps of my
| F105, because in my tests it seems I don't notice if I add a
| small weight there.
|
| I still remember when I first used my first Mi Band 1, a
| forgotten fitness band that had no display, just 3 RGB LEDs that
| could even get specific colors based on the app that sent the
| notification. I could know right away when I got a blue Messenger
| chat that I needed to answer now, or a yellow Google Keep
| reminder that I could ignore until I got back to my computer.
|
| [0]
| https://www.reddit.com/r/pebble/comments/9xw2j2/im_looking_f...
|
| [1]
| https://www.reddit.com/r/smartwatch/comments/174hq9x/need_a_...
|
| [2]
| https://tildes.net/~tech/18nf/smartwatch_primarily_for_notif...
| 0xEF wrote:
| I still rock my OG Pebble and while I am excited they're coming
| back, I have no plans to upgrade.
|
| Like you, my needs are simple; vibrating alarm, notifications,
| but with one key factor; I need a display that I can read in
| broad daylight that plays nice with my far-sighted eyes. The
| eInk display on the OG Pebbles hits the mark. Being able to
| read a text without pulling out my phone is also nice.
|
| Plus they can be got on eBay for about $30 USD and a fresh
| battery is about $15, so they don't break the bank. The
| Rebble.io community's work is still functioning well enough for
| my use, as well.
| Knork-and-Fife wrote:
| Small correction, pebbles use a TFT "e-paper" display, not
| e-ink. This is how they have reasonable refresh rates for
| animations and no after image problems. It's the best
| compromise imo
| MrAlex94 wrote:
| Would Withings[1] watches not fit the bill? I have a ScanWatch
| and the battery life lasts almost a month.
|
| 1: https://www.withings.com/
| alin23 wrote:
| The Scanwatch Light seems to be very close to what I need.
| While they're priced reasonably for what they offer, they're
| crazy expensive for what I would need. I'm really not
| interested in fitness or sleep tracking these days anymore.
|
| I'm also a bit scared of the many "charging issues" some
| people seem to have with them after a few months, but I guess
| every batch has a few bad devices so I could hopefully return
| it.
|
| Thanks for the recommendation! I might try one soon.
| MrAlex94 wrote:
| For what it's worth, after I bought one, around five other
| people I know got them, varying models from the Steel HR to
| Nova, and haven't been made aware of any issues. Of course,
| personal experience doesn't apply to the mass of products,
| and these are all UK SKUs, so who knows if issues vary
| between countries as well?
|
| Overall everyone has been happy though and I haven't seen
| Withings come up on HN which is surprising tbh!
| rstuart4133 wrote:
| [delayed]
| mrweasel wrote:
| Apparent my wish for a fitness tracker that's not a watch is
| also pretty niche. I know that there are rings, but I also
| don't like rings.
|
| Basically I want a bracelet, if it must be on my arm, but
| ideally it would be an ankle bracelet. I'm not sure that would
| provide a convenient spot to get heart rate, or data beyond
| steps.
| ramses0 wrote:
| Whoop.com, your wish has been granted! Just pony up $19.95/mo
| (or whatever) as well...
| mrweasel wrote:
| So close... but why the subscription? It just needs to
| stuff the data into Apple Health when it is within range of
| my phone.
|
| It is actually tempting, but I can't support a subscription
| based hardware product. Just charge me whatever the device
| cost + profits.
| hombre_fatal wrote:
| I've had one since October and really like it.
|
| I justify the ~$20/mo the same way I justify a gym
| membership: it's a bargain if it's compelling you to make
| positive choices about health/sleep/exercise. If it's
| not, then yeah, it's just an expensive mood ring.
|
| Of course, there are also smart rings (Oura) and much
| cheaper devices (FitBit
| https://store.google.com/category/trackers).
| ramses0 wrote:
| Same boat, Apple watch has terrible UX (1cm fingertip in a 2cm
| screen??!?), tries to do too much and not to my liking.
|
| Pebble allows me to walk away from my phone because I will get
| the notifications (text or phone call) and can see enough to
| decide to respond.
|
| Pebble is pretty lightweight and if you load up this watchface
| you'll feel right at home: https://store-
| beta.rebble.io/app/52f0939b1ac7948708001fc9
| lmm wrote:
| As per your last link, the current Mi Bands fill that niche
| pretty well. Screen, but decent battery life and small enough
| to not get in the way.
| dsalzman wrote:
| I agree. I've been looking for a "smart" watch strap or strap
| clasp I can use with my vintage seiko watch. I just want
| vibration alerts when very specific things happen on my phone.
| My wife is calling etc. Dont need all the features or display
| of a typical smart watch. Too distracting.
| K0balt wrote:
| This might be out of scope, but citizen makes the W770, I
| recently bought one for <200US lightly used. It manages to be a
| pretty good chronograph , BLE with an alarm and vibration motor
| (with a somewhat neglected strange little ecosystem of
| scriptable notifications).
|
| As a watch, it does require that you read the manual completely
| to understand its various interface paradigms, but it's
| reasonable given that there is no display per se, only hands,
| to show all of the information. Also, you may need to
| synchronize the hands at first setup, that baffled me at first
| lol.
|
| It's efficiently solar powered using a super capacitor, with
| months of battery life if left in the dark, no battery concerns
| at all if you wear it (unless maybe you are an actual vampire
| that also cannot tolerate artificial light)
|
| The supercapacitor can be replaced if it wears out, seems to be
| reliable for about 15-20 years based on their other watches.
|
| I like mine quite a lot, it's a well built actual timepiece,
| put it on and forget about it if you want. It doesn't ask you
| to do anything for it to just do its job, year after year.
|
| Citizen may have other options as well with BLE, idk.
|
| Id love to see someone reverse engineer the notification / BLE
| communication protocol and create an open source companion app
| - the possibilities for hacker-y types would be pretty cool.
| crote wrote:
| > I want a dumb watch with vibration notifications.
|
| Same. Notifications are _rarely_ time-critical. A few years ago
| I noticed that I kept getting distracted by my phone alerting
| to some nonsense which really didn 't matter, so I completely
| disabled all notifications. I'll just look at it once every few
| hours to respond to incoming messages.
|
| A regular smart watch would be pretty pointless for me. Getting
| stuff like message notifications on my wrist would be a huge
| anti-feature. However, it _would_ be pretty nice to have a
| convenient way to set an alarm, which will vibrate on my wrist
| when it goes off. I want a "leave now to catch the bus"
| reminder, or a "it's time to take a break" reminder! That's
| all, nothing more, no need to add any fancy sensors.
| Chris2048 wrote:
| > I kept getting distracted by my phone ... so I completely
| disabled all notifications
|
| Couldn't you just disable notifications for the unimportant
| apps?
| bornfreddy wrote:
| For me at least, it turns out there are no important ones.
| stateoff wrote:
| More information on the chip here: https://www.cnx-
| software.com/2025/05/14/sifli-sf32lb52j-big-...
| rgoulter wrote:
| "The SDK is open source" Oh, a BLE MCU with open source code SDK?
|
| AFAICT, the BLE code is provided as a binary blob.
| https://github.com/OpenSiFli/SiFli-SDK/tree/6c82a9b15db49871...
|
| Which isn't a problem. But, I wish if something is described as
| "open source", you could read the source code for it.
| pjc50 wrote:
| BLE radio device firmware is always going to be provided as
| binary blobs for a combination of IP and regulatory reasons.
| WJW wrote:
| I know very little about bluetooth firmware beyond using it
| for apps and such, but what kind of regulatory reasons are
| there that prevent publishing source code for bluetooth
| radios?
| tcbawo wrote:
| To avoid intentionally or unintentionally interfering with
| frequency spectrum it should not be.
| archi42 wrote:
| The BT blob (or WiFi blob, or general radio blob) often
| controls low level aspects of the actual RF device. So you
| can often alter frequencies, power levels and other
| parameters. This results in the device acting out of spec.
|
| Now one might say that's the fault of the person doing the
| modifications/manipulations, but regulations in various
| countries require the device to prevent these
| manipulations.
|
| (N.B. I'm not in the exact business, but that's my take
| away from looking into the topic some time ago)
| HPsquared wrote:
| Surely it's possible to maintain control over that while
| still publishing the source code? Seems like security by
| obscurity.
| ratatoskrt wrote:
| I don't know, I don't think there are many open-source
| third-party firmware implementations for these kinds of
| chipsets out there, so it seems pretty well obscured.
| barrotes wrote:
| Exactly my thoughts. To avoid out-of-regulation tweaking
| coudn't they just allow signed code to run? How can I be
| sure that this closed for, i.e. surveillance reasons? One
| can publish the source code and still prevent misuse
| afaik.
| wkat4242 wrote:
| Many modern chips do in fact use signed firmware yes.
|
| Technically they could publish the source in that case
| but I think some patents would prevent them from doing
| this. Radio stuff is riddled with patents. Also most
| likely the "why would we" reason. There is no benefit for
| the manufacturer.
| HPsquared wrote:
| Why would patents prevent open source? As in, they're
| afraid of patent trolls trawling their code for
| "infringements"?
|
| If it's concerning their own patents, no need to hide the
| source code. A patent is literally "letters patent" or
| public description of an invention. Trade secrets on the
| other hand I could understand.
| wkat4242 wrote:
| It's often a condition of licensing those patents. NDA's,
| they're huge in the radio and embedded world. It only
| became a bit more open when the Arduino and Raspberry
| projects came along. And even there it wasn't fully open,
| especially with the Raspberry because Broadcom is one of
| the worst offenders.
|
| I'm surprised how much they were able to open source as-
| is. I think part of that is that the SoCs powering the
| raspberry are kinda 'old news', definitely not the
| bleeding edge kind of embedded tech. The first raspberry
| basically happened because Broadcom had a whole bunch of
| old chips they weren't able to sell. Only when it took
| off they started making some actually for the purpose.
| sampullman wrote:
| That was my takeaway as well when I was working with
| Bluetooth modules a few years back.
|
| There were a few more reasons too, at least at the time.
| The companies in the space didn't have a culture of open
| sourcing, and there's probably no perceived commercial
| upside to releasing code for a chip like that.
| ratatoskrt wrote:
| I think often it's also a combination of what you
| described and big companies being super risk-averse. Why
| risk breaking regulations if you can just say no?
|
| Then again, lots of Wi-Fi-enabled devices support simply
| changing their region setting and will happily let you
| use different Wi-Fi bands or increase signal power.
| wkat4242 wrote:
| True but those bands are still official wifi bands
| _somewhere_.
|
| On software-defined radios you can often use them way out
| of spec, way more so than using a forbidden channel. But
| in a totally different band. A good example is the RTL-
| SDR stick which was designed to be a TV received but can
| be used as a wideband SDR these days. That's a receive-
| only device so it's not that critical to regulators. Once
| you can transmit, it becomes more of a problem.
|
| An example of a more problematic transmission device is
| the Raspberry Pi PWM pin. That's been used to transmit
| all sorts of stuff on many bands. Because it was never
| designed to transmit anything, it causes all kinds of
| weird harmonics and artifacts. It's a really bad idea to
| use it for that. Most people just do it under controlled
| circumstances.
| cik wrote:
| To be fair, depending on your partnership you actually do
| get the code to these blobs, and export control comes
| into play.
| moring wrote:
| I understood the criticism to be about describing it as open
| source when it isn't, i.e. that
|
| "We say it's open source because we expect the reader to know
| that we're not telling the truth"
|
| should be replaced by
|
| "It's open source except for the BLE firmware blob, which
| can't be open source due to regulatory reasons."
|
| To be fair, the article just repeated the claims made on the
| GitHub page for the SDK.
| introiboad wrote:
| Not in Zephyr. There's a full BLE Controller in source code
| form there.
| 5ADBEEF wrote:
| Zephyr provides an open source implementation of all layers
| of the BLE stack. The radios of some devices are documented
| extensively, Nordic nRF5 devices are probably the best
| example.
|
| The Bluetooth SIG requires that you qualify your device if
| you advertise that you use Bluetooth IP, similar to what is
| required for the cellular space. Do you have to do this if
| you're just "Bluetooth compatible?" Maybe not. Whatever the
| case you have to conduct FCC part 15C testing (intentional
| radiator).
| solarkraft wrote:
| > you have to conduct FCC part 15C testing (intentional
| radiator)
|
| Maybe soon you won't.
| zwirbl wrote:
| Care to elaborate?
| hermitShell wrote:
| Maybe orange man will abolish the FCC because rules are
| inefficient
| amelius wrote:
| > The most interesting and difficult constraint is actually
| software compatibility.
|
| But it is probably the easiest constraint to get around. I would
| put this one more towards the end of the list.
| ItsHarper wrote:
| There's two big factors that make software compatibility very
| important for this product specifically.
|
| 1. His team is positively tiny compared to what Pebble used to
| have, and the less software work that's needed, the better.
|
| 2. All of the apps and watchfaces people wrote for the original
| Pebbles were distributed as compiled ARM binaries, so if you
| picked an MCU with an entirely different instruction set, you'd
| lose backwards compatibility. ESP32 would fall into that
| category, for example (not that it would have been a good
| choice anyway).
| amelius wrote:
| I mean, these applications are by necessity very tiny. They
| must fit in a very small memory. Hence, I seriously question
| that it would take a lot of work to rewrite the software for
| a different architecture. You can reuse the entire graphical
| design (which is probably a large chunk of the work because
| designing for small screens is not easy).
| mrheosuper wrote:
| There are solution for question 2. You can either add a
| compatibility layer to the software stack(something like Java
| VM), or people can build their app against your codebase, and
| your watch will dynamically load it and run(like how linux
| run their app). In Zephyr they have LLEXT for that.
| mkesper wrote:
| Not at all. If everything is proprietary you will run into many
| dead ends. This is totally different than with e.g. standard PC
| hardware.
| rjmunro wrote:
| PebbleOS isn't the only player in this space. There's also
| https://www.espruino.com/ which powers https://banglejs.com/.
| It's a tiny implementation of Javascript for microcontrollers, so
| it's really easy to hack your device in real time.
|
| It also powers the Fallout Pip boy and possibly some other stuff
| from the wand company: https://www.thewandcompany.com/fallout-
| pip-boy/ See: https://github.com/orgs/espruino/discussions/7577
| swyx wrote:
| appreciate the shouting out of good work for lower profile
| competitors. Pebble is awesome but they deserve some love too.
| thx
|
| also everyone watch the Amazon Fallout show if u have the
| chance its p good
| sabellito wrote:
| Had never heard of bangle js, love the idea of fiddling with it
| with a languange I already know. Would love to buy the 1st
| version, as I don't like square designs, but it seems they
| don't sell it anymore.
| outadoc wrote:
| Thank you for the write-up. Cool to see some degree of open-
| source hardware running PebbleOS.
|
| Though, can we stop having left-aligned blogs in 2025? Wide
| screens have been here for a while, it makes it unnecessarily
| hard to read :(
| wkat4242 wrote:
| This smartwatch isn't really all that smart by today's standards.
|
| I would really miss the mod cons I have on my current smartwatch.
| Payments over NFC, dual-band GPS tracking, 4G LTE connectivity.
| The Pebble (and repebble) trades all that in for a multi-week
| battery life. But the minor hassle of once-every-two-days
| charging on my galaxy watch really isn't enough to forego all
| these powerful features for me.
| micromacrofoot wrote:
| It is for me, I don't care about any of those features. I just
| want a watch I can customize a bit that gets notifications and
| can do rudimentary heart rate monitoring. If I have to charge
| it more than once a week I won't wear it.
| me_online wrote:
| The battery life alone suggests otherwise.
| dwayne_dibley wrote:
| I too would miss GPS, BUT I've still never found anything that
| really fills the pebble shaped hole in my life. My Garmin
| compromises the other stuff (battery, widgets, calendar,
| display readability etc.).
|
| Everything is a trade off.
| bigstrat2003 wrote:
| Conversely, I don't care about any of those features, and I do
| care about long battery life. It's great that different devices
| catering to different users exist. I don't think the fact that
| they are aiming at different users from you makes it "not
| smart", it just makes it not suitable for your use.
| wkat4242 wrote:
| Don't get me wrong, I backed the first Pebble on kickstarter.
| Still have it. It was a great watch for the time. I loved it.
|
| But these days I just have bigger requirements. The whole
| heartrate thing I don't even care about. Notifications are
| the main thing, but route tracking, integration with my alarm
| system and above all payments are just things I can't do
| without anymore. I had an Amazfit for a while which also had
| a 3-week battery life (though no apps) but it missed the
| payment option.
|
| The charging is not a big deal for me because I only wear my
| watch outside anyway. And it charges in 30 minutes. It makes
| it easy for me to keep it charged also because it becomes a
| routine. With the amazfit it was often empty when I needed
| it.
|
| But yeah it is great that there are devices for everyone.
| pedalpete wrote:
| I'd add that it also ignores that Garmin already has multi-week
| battery life with most of these features and more. The only
| thing they don't have is 4G yet, but I believe next year's
| devices have been reported to have it.
| Shalomboy wrote:
| Love this write-up. nimBLE is a great bluetooth stack; this
| should open up some interesting opportunities for Core Devices
| moving forward.
| zoobab wrote:
| I started to hack around cheap chinese Freqchip SOCs:
|
| https://github.com/zoobab/FR801xH
|
| You could get smartwatches for 3EUR on Ali with this chip.
| ENadyr wrote:
| Wow, some of these chips are 2.6rmb at 3k MOQ ($0.36) for an
| Arm Cortex m3 with BLE (and sig-mesh) support... this is
| wild!!! How usable is the SDK?
| ENadyr wrote:
| @ericmigi these are great BTW, wish you did them during YC while
| we were going through all these decisions haha
| aswanson wrote:
| Awesome feature set for that price.
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