Computers vs smartphones - myth busted

Over the last year I’ve went back and forth on buying my first bike computer - I fancied the wahoo bolt.

I’ve never been sold on the merits of computers over my smart phone. I’ve Googled the subject a few times and I’ve seen a lot of outdated answers that just do not apply to modern mid/high end smart phones.

After Strava’s latest doozie (removing sensor integration) I figured now might be the time to take the plunge. Before I spent the £200 I figured I’d go on something of a test ride with my smartphone and see just how much power my cycling app of choice munched through, seeing as this seemed to be the main argument against smartphones.

Basically the result has me unable to justify spending the cash on a computer.

Here’s how my ride went yesterday:

Charged my one year old Samsung galaxy S9 100%, closed all apps, no power saving other than set display to hd+ (which I always use anyway). Switch on GPS, open the wahoo app and connect my heart rate and cadence sensors and away we go.

With the app running for my full 3hr20m ride, display always on and the screen brightness turned up just under half way (to the point where it was at least as clearly visible in daytime as the computers I’ve seen) I arrived back home 50+ miles later with a battery that was still 56% charged. That’s with me taking a couple photos and messaging the wife aswell.

So i feel we can dispel the myth that GPS and cycling app destroys modern phone batteries. Of course if you are doing super long rides of 7+ hours then yes, your phone is gonna die. How many normal, average recreational cyclists do rides like that?

As for other arguments I’ve seen against smartphones let me take a stab:

  1. The rain messes up my display/destroys phones; as far as I’m aware phones have been waterproof for years now.

  2. I don’t want to damage my phone in a crash; How often do you crash (again, as a recreational rider) and is it that bad a phone attached to your stem is gonna take the hit? Also, is it OK to destroy a £200-£400 bike computer but not OK to damage a phone that may be insured against damage anyway? For the record I have logged about 6000 miles in the last year and not come close to crashing.

  3. My bike computer is tidier and more aerodynamic; quadlock will sell you an attachment that allows you to place your phone out front like a computer. Personally I use a quadlock on my stem - once locked in the phone sits nice and tidy and doesn’t move. It also takes all of a second to dismount it for photos etc.

  4. I need the ride data the computer gives me; really? Have you not delved into some of these free cycling apps? The wahoo app itself gives you a ton of data after your ride to pore through if you so wish. You can also head onto your pc on some of these apps to go into even greater detail.

So that’s kinda my feelings on the subject. I’m a giant man-boy who wants the next shiny toy for my hobby but I can’t rationally justify the purchase no matter how I look at it.

I’d love to hear other recreational rider’s opinions on the subject.


Personally I’d find it hard to argue with any of the four points you’ve raised.

The reason I don’t used my phone is very simple. I want to be as certain as I possibly can that should the worst happen to me or a ride buddy, my phone has enough juice to make a few important phone calls.

Yes, maybe I am being a ‘snowflake’ but I’d rather not put myself in the situation where it does become important. Add to that the fact that my phone also displays my critical data, should I be found in a ditch, I’d rather save the battery.


Yep I have similar thoughts to @PusherMan (and I fall off quite often) Plus I do Ironman which does not allow Smartphones so I need a computer anyway


I get that wildwill - if I raced at all I’d use a computer too.

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This. A few smart phone generations back I tried using one just to track a ride and the battery died 3/4 of the way around. More recently Garmin livetracking through my phone did the same thing by burning it all up on the BT connection. While these are just first world problems here they did cause my family some undue stress as they speculated about the reason my marker had stopped moving around the course.

So in an attempt to assuage their fears I duped myself into going for a Hammerhead Karoo… two years on it still doesn’t really work: no live tracking or workouts, GPS barely stable. Mind you I did hack TR onto it at one point… Didn’t really work either. Big lag on the ERG feedback and the in-ride instructions weren’t legible… And the battery never lasts more than 5 hours anyway… Lovely paperweight.

Still YMMV

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My phone isn’t waterproof (Honor 10 - splashproof but not waterproof).
My phone certainly isn’t mud-proof, and I crash pretty much every time I ride a muddy CX course (often more than once). I crash less when training, but that doesn’t stop it getting mud thrown at it.
My GPS cost £115, and the phone was almost £300.

I can’t really comment on a Hammerhead Karoo but I feel like 3 messages in and the point I’m trying to make, the fact that for most people phone battery wouldn’t be an issue is already being lost.

How much juice do you need in your phone to dial emergency services or your significant other?

Is there more of a chance that phone will in fact be damaged if it was in your jersey back pocket as opposed to your bike’s stem?

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As I said YMMV. I have been using bike computers since before mobile phones and for me it was a deal breaker that it ran out of juice when I tried it. Still will if the screen is left on. I don’t see any myth issue here. Use a smart phone if works for you.


I like your approach, I think you’re 100% correct.

The main thing I see stopping people using their phones it’s probably a “coolness” thing, masked by excuses of battery life or similar.


A phone is not designed to be sat on handlebars and who the hell wants that great big lump on your bars anyway? I’ve see this argument numerous times, especially from newer riders, they start with the phone because that’s what they have (fair enough), 6-12 months later, they have a Wahoo or Garmin. Why? Because it makes total sense to use something that’s been designed for the purpose.


There’s no right or wrong answer here. There’s no myth to bust. Your choice is going to depend entirely on your phone, your budget, and your environment. For example:

Mine isn’t. It’s also not road-grit-and-mud-proof. It would need to be in a thick waterproof bag.

I decide against this reasoning when I put on a helmet.

My Bolt was around $200; my phone is $700. The Bolt is about 1/3 the size and mostly sturdy plastic. I could throw it, with force, onto a concrete floor, and it would bounce and be fine. The phone is a phone. I cracked the screen once dropping it from about 18" onto a hardwood floor. It’s not insured, and the 2FA app I use means it’s required on a daily basis.

Sure, where it will stick out an extra 4" or so, making it much more likely that I’ll accidentally knock it into something, because I’m a klutz, which will cause damage, because it’s a phone.

If it’s in the back pocket of my jersey, half of it is protected by my body, and the other half has a layer of jersey covering it. I’d also have to fall on my back, or get flipped upside down, to cause damage. On the stem, really any crash is going to smack the phone into something hard.

All of that said, I used my phone for ride tracking (in the back pocket of my jersey) until I decided I wanted to see my speed/cadence/heart rate in real-time. I still use it sometimes if I don’t want to faff around with all the monitors.

You do you. There is no universally optimal ride tracking solution.


Never wanted a bike computer, the obviousness of smartphones and smartwatches make all of those specialist devices a dying niche.

Unfortunately Ironman races banned mobile phones on course, so a bike comp I now have £200 only used a few times per year…


OOooo interesting, why?

A great big lump like a garmin 1030 you mean?

Yeah I’m not a fan of those either.

I can’t help but feel that your 3hr ride example was a little disingeneous? Or maybe this forum is the wrong audience for your example? That is way too short to not be a source of stress especially on those days where cycling-wise we are doing something out of the ordinary like a multiday bikepacking trip or even just the monthly 200km loop. I think our equipment is purchased based on our needs during those special and epic rides not the everyday ride.

Also, I’m not comfortable doing any kind of off-road or gravel with my phone on the handlebars.


How is it disingenous? He’s sharing experience of his test. Maybe this is a long ride for the OP.

Also bear in mind that if you’re doing multi day bikepacking then your garmin/wahoo battery is still going to need to be charged in that time.

Most phones mount to the handlebars with the same mechanism as a garmin so your phone flying off is only as likely as a a garmin flying off. And if you crash, the device is protected from all sides so it’s highly unlikely to get damaged whether you have a phone or a garmin attached

No not really… I regularly ride in excess of 5 hours over the course of a year. No phone can go there for me. I have cracked phone screens from 12 inches dropping onto a desk. I crashed plenty of times where my garmin bounced down the road with less damage than I had. I am not happy leaving my phone out there. In its case in my pockets is good for me. I have, in all my years, never managed to get road rash on the small of my back yet. Cue ominous music…

No outside communication allowed.

Plus it stops people running around filming selfies in the middle of a race :+1:


The OP’s testing would suggest a total battery time of somewhere around 7hrs so maybe you need the same phone as him :slight_smile:

If you haven’t crashed on your back then why put the phone in a case? :wink:

For what it’s worth, I use a wahoo bolt, and have used garmins previously. But when I think about the reasons for choosing these rather than just using the phone I already have, its difficult to justify.

If someone wants to say “I choose to have a garmin because I prefer it or because I can” then I don’t have a problem with it. It’s only when people create flawed reasons for justifying it to themselves that I question them. It’s the same with bikes. If your average club rider wants the latest 10k venge “because its cool” then I have no problem with it. But if they have one “because it saves you 3w at 40kph due to new aerofoil design etc etc” then I can’t help but chuckle.