Dedicated bike GPS computer over smartphone

Question

Yes, I know it's a duplicate of questions that have been asked before, for example this one: Are there advantages of dedicated bike computer instead of smartphone apps?

But I feel that most of the reasons given 8 years ago in response to this question have been invalidated:

• The phone is larger → yes, but you still have to have it with you

• glare → max screen brightness has improved a lot in recent years

• not designed to sit out exposed to hot sun, extreme temps, and rain → not really true any longer, with the arrival of IP67/68 resistant phones

• ease of use → new phone apps like Komoot, Strava, MapMyRide, etc. make the phones seriously better for bicycling than 8 years ago

• battery life → much improved, with a new iPhone I'm getting at least 6 hours of use on the bike, and that's with the Komoot navigation on; for longer rides, it's easy to pack small power banks.

So my question to anyone who is still using and paying for specialized bicycle computers like Garmin and Wahoo, in 2019, what are you getting out of them that a contemporary smartphone doesn't give you?

Answer 1

I used a phone for about two months, then bought a Wahoo GPS computer in March 2018. The primary motivation was that

• My phone has lousy GPS (Huawei P10). Multiple times a week, it would claim that I'd teleported half way across town, lose signal and never get it back, or drift so that the track would look continuous but end up hundreds of meters from my destination. I hear that iPhones have pretty good GPS. My Wahoo has near-perfect GPS; the worst it does is beep at me in forests on cloudy days because it thinks I've wandered too far off the side of the road. Some speed sensors can talk to phones by Bluetooth, which may improve phone (and cycle computer) tracking accuracy.

Other advantages:

• Size and mounting. My phone isn't big, but it's much bigger than my Wahoo and I found it somewhat inconvenient on my handlebars.

• Battery life. My Wahoo claims 15hrs. I probably get more like twelve, but that means I only need to recharge it about once a week. Six hours of battery life would mean that, if I set out on a 4.5hr ride without having my phone fully charged and things took longer than I was expecting, I could easily be caught an hour away from home with no GPS and no way to call for help. Which is to say...

• Redundancy. Having a cycle computer and a phone means that I have one device to keep me safely on the right track and a separate device that will give me backup navigation and, in the worst case get me help.

• User interface. The Wahoo has six buttons. While I'm riding, I can press the buttons to get to the screen I want without looking, and then glance at the computer to find out what I need to know. Touch-screen navigation of the phone requires you to look at it and is awkward when things are bumping around. I put the phone inside a waterproof pouch (because, England) but found that made the touch screen awkward to use. Touch screens are a pain with gloves, too.

• Crash resistance. The one time I've crashed, my Wahoo (and my knees and shoulder) got scuffed up against the concrete in a way that I'm pretty sure would have wrecked my phone, but which caused only cosmetic damage to the Wahoo. My phone was in my jersey pocket and was completely undamaged and available for use if I'd needed to take photographs or call an ambulance, or a friend or taxi to get me home. Of course, one can easily imagine a crash in which the contents of one's jersey pocket get trashed, while stuff mounted on the handlebars survives. On the other hand, the phone felt much less secure on the handlebar than the Wahoo does.

In other words, not much has actually changed. The only thing I've not mentioned that came up a lot in the previous thread was screen brightness. I guess my phone's screen brightness would probably be fine, but it was kind of moot, as I never did figure out how to stop it blanking the screen after a few minutes of riding. I'm not sure how my phone would have coped with being in its waterproof pouch on a really hot day; I only used it in the English winter.

Answer 2

I use a phone for navigating long rides (up to 400km/20 hours). I'm rare among distance riders, and if I had unlimited money might get a dedicated unit. For me the phone works well - a dynamo keeps the battery topped up, I've got offline mapping and setting the screen brightness manually means I'm not dazzled. I don't (usually) have turn by turn navigation, but following a line on a map suits me and I can import gpx files.

So why would I use a dedicated GPS?

• The biggest issue is touchscreens and rain. My phone is fully waterproof but heavy rain makes the screen unreliable (big drops detected as touches, for example). I've made a little windscreen that helps a lot while moving forwards, but doesn't do much in stop-start conditions.
• Having the phone as backup navigation would be nice - I probably carry more weight/bulk in maps/route sheets than a basic GPS unit (some form of backup is essential for what I ride).
• Occasional all-night rides do require an external battery (9pm start in winter, riding 340km through the night and the whole of the next day) as my dynamo runs my lights after dark. That would also be the case on a GPS, and some of those don't like to charge while riding.

Answer 3

Main reason not to use you phone has to be cost and crash resistance. While a dedicated unit may set you back $250-$350, many people have a decent phone with a replacement cost of over $1000. Given the number of phones I see with broken screens, the crash resistance of a phone has to be considered less than ideal at best. A dedicated unit is not only significantly cheaper, but also far more crash resistant.

For someone who Mountain bikes, a phone on the bike is going to work out more expensive than a dedicated unit. For many the risk of crashing is low enough its an option.

Answer 4

In addition to all the other advantages a dedicated cycling computer has over a phone, battery life when collecting data from wireless sensors such as speed and cadence sensors and power meters is much better with a cycling-specific computer compared to a smart phone.

ANT+ is designed for low power consumption, so battery life for ANT+ components is much better. And that longer battery life doesn't only apply to the dedicated cycling computer - it applies to the sensors, too. I've had to replace the battery on my ANT+-only SRM power meter only twice in the 8 years I've had it. I've had to replace the battery on my PowerTap C1 crankset that transmits both Bluetooth and ANT+ three times already in the six months I've owned it. And I'm not riding anywhere near as much as I was when I first got that SRM. Back then I was averaging 50-60 hours per month. Now I'm at more like 20-30.

Another benefit that I haven't noted mentioned yet - try using your touch-screen phone while wearing heavy gloves or even mittens because it's -5C. A touch-screen cycling computer is designed to handle gloves and even mittens just fine. Nor does a cycling computer go crazy from misinterpreting rain drops as "touches".

As a cycling computer, a phone makes a pretty good phone. For a lot of reasons.

All the mental gymnastics in the universe can't make a general-purpose device that has to have a relatively fragile and large screen work as well as a device dedicated for the purpose.

Answer 5

I work for the world's largest bike parts distributor, and we sell a lot of Garmin equipment. The appeal, especial with Garmin (and what they're pushing) is the device independence and precision. If you buy a Garmin, that device will literally be supported forever, and with quality that meets and exceeds military / naval standards. I have an old Garmin from 1995 meant for surveying, and the software will still work in windows (albeit in compatibility mode). No phone does this. Not even your top of the line Samsung and Iphones.

Now my education is in electrical engineering, so let's allow for room there as well. The GPS on your phone is, at the very best, Half-arsed. It really has to be, as, for example, the Samsung galaxy s9 has the board area equivalent to about 2.5 SD cards, and likely 8-12 layers of copper traces. With all of these traces carrying information, It's very difficult to actually read a GPS signal. at the best of days, you'll likely get accuracy with a radius of 2 meters (6.5ft), and that's with a clear shot of the sky. With a dedicated GPS, you get much more consideration into the GPS itself, and as a result, the accuracy (on the best of days) can get as low as 2 inches, and if you're using some of the fancy tech that the DNR has, 2cm. On the more overcast days, you'll get 2-3 feet.

If you're a data nerd like me, increasing accuracy by such a factor is an amazing benefit, especially if you're off-roading and there's no trails that you can snap your results to. In a road situation, you probably would not need more than a phone. almost anywhere else, it's worth your money. I highly recommend a detachable one, as then you're not limited to just your bicycle.

Answer 6

My old GPS was powered by AA batteries. No need for recharging in the field (powerbank or so), you can just take a sealed pair of alkaline batteries with you so if something unforseen happens, the trip takes much longer than expected, you have at any rate still backup power to navigate. Even if you'd forgotten those, you could easily get fitting batteries at any supermarket or gas station and can immediately continue with navigation.

(The batteries I was actually using normally were NiMH, and I recharge those.)

Well, that old Garmin eTrex broke last year, and I then got a more modern, powerful, and internal-lithium powered one. The new one is better in most regards, but I am rather more anxious about battery life now than I used to be.

For another thing: I personally reject phones out of principle. Google, Apple or anybody else has no business knowing where I go with my bike.
Clearly, this doesn't bother 98% of other people though, so...

Answer 7

I use a Garmin 510. I keep telling myself that I will retire it for the newer 520 when it breaks but the darn thing won't break.

When I ride, I don't want to be interrupted by life outside of my bike. Yes, I will always keep a phone on me for all rides for emergencies and to send my location to my wife, but it will be on silent and tucked away safely in my back jersey pocket. I turned off all notifications on my Garmin watch as well. This is my time, whatever happens off the bike I will get to when I finish the ride. By the way, that is also the way that I drive too.

• Phone is larger, too large to be put on my handlebars. I have an Note 8 and although I will have it with me, it will be tucked in my jersey pocket.
• Glare is not a problem on my bike computer or my phone due to being a super bright phone but again, it is really big and very breakable.
• My phone gets hot in the sun and yes, it is water proof but not nearly as tough as my GPS Garmin. My Garmin has survived an accident that put me in the hospital for days. At the time I was using my summer phone [Samsung Active] and it was built to be tough but since I gave that one away, I have only a pair of Notes that I use. They aren't known for being all that tough and they are expensive. Would you want to strap a fragile $1000 devise on your handlebar that is so big that it could act as a sail?
• Ease of use. Sorry, doesn't get much easier than my Garmin.
• Battery life. My Garmin will last a 16 hour ride, long after I have given up.

Answer 8

I bought a Wahoo Elemnt a few month for a simple reason: cycling is for me the most demanding use of the phone, having the phone and cycling GPS separated is better on the long run and allows to choose phones that wouldn't be in the options if cycling is in the requirements.

While it is true that navigation apps have gotten better, cycling GPS have also gotten better. The main gripe I had with my old Garmin unit was to copy routes to the device, which isn't a problem anymore. Current devices synchronise routes automatically with popular apps, display notifications and provide the GPS measurements to the phone for live-tracking features. With navigation, I personally don't need more when riding.

Using the phone for cycling basically requires to take a large phone to have a large battery. Also, cycling causes additional wear on the phone battery: first because of the obvious use of the GPS and the display when riding. And also because direct exposure to sun heats up the phone and then the battery: exposure to heat also increases wear on the battery.

Another concern I have if keeping the phone "as long as possible" is linked to waterproofing. After replacing the screen or the battery, the phone can't be considered fully waterproof anymore. If you don't use the phone mounted on the handle bar, it can be stored in a place less exposed to water (waterproof pocket in a bag).

Regarding the choice of the phone, I prefer small phones, that have by design smaller batteries (that would also wear faster in case of heavy use). Given phones are now mature products, I also don't mind having an older model (I don't like the 'jewel' feeling when having a new phone).

To complete my answer with my 'purchase history': my main phone was an iPhone 7 Plus. After purchasing the Wahoo, I replaced the 7+ by a refurbished iPhone SE 2016 (with a new battery). When using Spotify (and live tracking from the GPS), the battery drain on the phone is about 8-10%/hour, and I can leave it plugged to a powerbank in my bag if needed. While there are some drawbacks (photos — size is for me a trade-off, not a drawback), I retain that the combo 'small phone + cycling GPS' works very well, if you don't need a large phone otherwise.

Answer 9

I use both - I have a $4 "cycle computer" attached to the bars of one bike. Its sole purpose is to display my current speed, and the clock. Those are literally the only two functions I care about. Its not even pretend-waterproof, but has survived 6 months. Being so cheap, the battery life is abysmal, so its going to get replaced with a low-end $20 Cateye.

The cheap cyclecomputer stays on the bike at all times. I don't even bother unclipping it when in a shop.

On the same rides, my fancyphone is tucked safely into my bag or jersey pocket. Its job is to run Strava and I don't touch it during the ride. Sometimes I ride with a HRM, but that info is logged by the phone, and I don't use it for training.

Would I use an expensive Garmin or Wahoo head unit? Definitely, if I owned one. But they're ridiculously expensive, easily costing 3-5x as much as my bike, so I couldn't justify buying one while other things demand payment first.

Answer 10

IP67/68 resistant phones do exist, but regular phones offer a much larger choice (especially if you exclude the non-rugged IP67 phones which are not quite comparable to bike GPS in terms of protection). If you want to use your phone as a bike GPS, you will be limited to those sturdy phones. And such phones themselves result from a compromise between the sound / microphone quality (which require more holes and/or larger holes) and the IP rating (which ideally requires to have no holes at all).

Bigger weight of the phone is also a significant disadvantage which is not completely countered by "you still have to have it with you". Having extra 200 grams in the backpack is rather insignificant, while having extra 100 grams (200 grams phone instead of 100 grams bike GPS) mounted on the handlebars does make a difference: the amount of shaking you can take is reduced by two, assuming the same mount quality.

Answer 11

Many answers mention battery life as an advantage to dedicated cycling GPS units. However, this issue hasn’t been explicitly addressed yet: on phones, the screen is a major drain on battery life. Phone screens are usually on standby. Cycling computers use much simpler screens with lower power consumption. Thus, if you value being able to see your statistics or your mapping software without having to take an extra action, the cycling computer is clearly superior. This isn’t critical functionality for all users, however! It depends on the use case. A casual cyclist may have more than sufficient power on their phone, and they might only occasionally check a map.

People have mentioned durability of the phone in a crash as a concern. Dedicated phone mounts with cases, e.g. Quadlock, can offset this concern. Remember that most cyclists don’t crash often, and of the times we do crash, a phone in a hard case that’s secured to the bars may not take damage. This does depend on having a secure mount, and my understanding is that Quadlock is pretty secure. I have no personal experience with them. I believe that they have at least a few credible competitors, but I can’t remember which ones.

Answer 12

I do use an iPhone rather than a dedicated head unit, but I think I can speak to some of the drawbacks (and non-drawbacks) of using a phone.

• Mounting options: It is possible to mount your phone like a bike computer, but its weight and moment of inertia on the mount are too much for some mounts; it also may not fit between the stem and some out-front mounts. In short, your options are a little more restricted.
• Data displays: On a smartphone, you're limited to the data fields that the author of the app your using has chosen to make available (which can be extensive, but are not extensible, AFAICT). With higher-end Garmins, you can add new data fields that can be calculated from your existing data sources, and out of the box, Garmins have some interesting displays, like detailed hill gradients, that I haven't seen in a phone app.
• Compatibility: All modern phones support BTLE, all modern head units support this and ANT+. Most modern accessories support both. There are BTLE/ANT+ gateways available, but if you've got ANT+-only accessories, there could be more fiddling. The coin cell powering my chest strap runs for about one year.
• Always-on display. This is possible with a phone, but as mentioned, it runs the battery down a lot faster.
• Aesthetics: Some people think that having a big phone hanging off the front of the bars looks dumb. That's a matter of taste.

Smartphones used as bike computers have some advantages, or work better when not used as a direct replacement.

• Better navigation: You've got a big map, and there are cycling apps (RideWithGPS) that can speak turn-by-turn directions; head units will just beep at you to notify that there's a turn coming up, and you need to read the screen. Those spoken directions can be a big advantage when following a new route. Some people miss those beeps.
• Spoken stats: Instead of keeping the screen on all the time, you can have the app speak your stats at regular intervals. This isn't appropriate for all situations (intervals), and can be downright annoying in some (out-of-zone warnings), but it is a way the phone is different, not necessarily worse.
• Simplicity: There's a learning curve with any new gadget, and a need to keep it up to date. If you've got a smartphone anyhow, you can avoid that.

With the screen mostly off, a smartphone has plenty of battery life: I've done 12-hour rides with mine without recharging. Most modern smartphones are waterproof, so that's not a big consideration, although I've found that you can't charge an iPhone when the charging port is wet. Crashworthiness might be a reasonable concern, but I keep mine in a robust case, between a pair of aerobars, on a lanyard, so it probably isn't going to take any hard hits.

Answer 13

In my case, I went on a six hours ride in a hilly, forested area (where GPS lost its signal), and there was a distinct lack of phone coverage (for an hour or so).
Surprisingly (or not), the Strava application recorded a ONE WEEK trip (which the Strava site wouldn't accept for uploading).
Also, I've had another ride where the GPS "registered" the ride 200 meters away from the road (part of it on a 70% incline :), and part of it through houses and gardens ) and a 140 km/h maximum speed (compared to the 60 km/h max or so recorded by the $20 bike computer). Now the speed sensors might be "slaved" to the mobile phone and be used by Strava to improve "reckoning", but usually mobile phone plus GPS application means no wheel speed sensors, no pedaling rate sensors, ...

Answer 14

Once we had scientific surveys (in the middle of the desert) with the teams using mobile phones (with specialized software) and also Garmin devices (for positioning). Since then I remember that navigation devices were easily readable in very direct and bright sunlight, when nothing was visible on the phone without raising it close to the eyes and covering with hand from the sun.

Probably some different technology is used for displays that work in the direct sunlight.

Answer 15

Other answers cover other issues very well, and the question kind of mentions this, but I think it's still a valid concern.

I have an iPhone 7 Plus - so not the newest smartphone in the world, but still fairly new. With the screen turned on, when exposed to sunlight, it can heat up a lot. This can affect performance and I don't think is without effect on the lifetime of the battery at least. Where I live, temperatures can sometimes exceed 45 degrees Celsius - and frequently exceed 30, and having the phone exposed to sunlight for hours at a time in these conditions is a no go. My Garmin, on the other hand, never really feels like it's overheating.

And, on top of that, it's got better GPS, better battery life, independent battery so it dying won't make me unable to make calls, is more handy and smaller, has a dedicated mount, integrates well with a whole bunch of sensors and so on and so forth...

Answer 16

Another good reason, maybe not fully bike related to use a phone instead of a bike computer, is that you can take pictures with your phone.

I used to use the quadlock mount with my phone, and it was very easy to remove the phone to take a quick picture.

Now, because I'm using a garmin device my phone is in my bag and if I need/want to take a picture, I have to stop, remove my bag, pick my phone, take a picture and reverse all that.

Even if my phone is in one of the pocket in my bike jersey, it is not as easy as picking it up from the mount.