So I've been using my cell phone for strava and it was working like a charm til I got a new update to the OS on the phone. After the update the reception is horrible, I come home and a bunch of segments were not recorded.

I'm using an android now, but I'm contemplating getting something like the Garmin 520. Are the dedicated bike computers' GPS better than what we find in a cell phone? Im guessing my issue will be resolved in a future update, but I guess I could find myself in a similar situation again when I rely on the phone..

Tldr: are bike computer's GPS signal better than that of a cell phone?

GPS in bike computers and in cell phones are receivers, not transmitters. The question is one of receiver sensitivity and resultant reliability and accuracy, which will depend on the chip(s) used, the antenna, and the processing and recording software, which includes the app being used on cell phones. In general, I find my cellphone to be as good or better than my Garmin devices.

Thanks for for the reply. That's alarming if the gps on a device that's built specially for this purpose isn't better than a cell phone.

Are you a iPhone user? I believe my issue with my phone stem from the new android os' (marshmallow) new doze function.

I wouldn't down play "cell phone" capability. These days they are very powerful, handheld computers. I use a Samsung Galaxy S6 with Strava and find it's GPS function very accurate and reliable. It seems to use far less battery power than I would have imagined when I started using Strava and the GPS for, so far, rides up to 4 hours. I know it is not the same model you use but...

Much better. The newer Garmins use a combination of GPS+GLONASS they achieve lock very quickly and are consistently ~1m accuracy (I can tell which lane uphill vs downhill). Battery life is also much better.

Cell phones do have a few extra tricks, such as using the tower locations to help the GPS lock faster.

I was very happy with my phone's GPS too until this new update, but when something like that can render it pretty much useless I was thinking the dedicated bike GPS/Computer would be the way to go. However, it seems like a pretty pricey update so I want to make sure it's an improvement.

It's not always a question of accuracy but recording rate. Garmins normally record a data point once per second. The GPS tracks I've seen from most cell phones don't record as frequently and the speed calculated by Strava based on a phone's GPS is much more erratic than what you get from an actual speed sensor.

I'm using various apps on an iPhone 4s that doesn't even have a data plan. I have an old flip phone for emergencies. Cyclemeter works fine for recording my rides to review later. The only thing it won't do while I'm riding is show me a map of my current location, but it will show my time, distance, etc. After I get home (or to any wifi hotspot) the app updates to include the map. It does what I want from a GPS app -- just records my routes to review later. Handy to repeat a good route, or avoid a route or turns that didn't work out well. It's remarkably accurate, rarely more than a few yards/meters off from my actual position at any time during a ride.

I tried Strava, MapMyRide and a couple others once or twice. Didn't care for 'em, but I'm not interested in realtime feedback for riding speed, competition, etc.

I might be able to use realtime turn-by-turn directions but I'll probably need a data plan for that. I haven't found anything that works just off GPS for turn-by-turn directions.

Same for my Samsung S5.

This may seem obvious, have you tried disabling the "new doze function"?

Yes, tried that already but still no go. Had some success today when I set the screen to stay awake and just dimm. I guess that might work for now, but Still eyeing a garmin 520 though.

I find exactly the opposite.

This will depend on a lot of things like (1) what phone do you have, (2) where do you use it, and (3) where is your phone while you record.

A cell phone is going to augment the GPS signal in a city with things like cell towers and wifi networks. Go out into the country and it doesn't perform as well.

An Edge computer out in front of your handlebars or a Fenix/Forerunner on your wrist is going to have a better view of the sky than a cell phone in a ziplock bag in your pocket.

The traces I get from my cell phone look like I must have been drunk, zig zagging all over the place.

I use an iPhone 5c with Cyclemeter as my bike computer. I do an annual ride across Florida and an annual MS-150 that take me to areas where there is no cell service and my GPS tracks my ride perfectly. As far as I'm aware of, I have never had an issue losing GPS signals since I've been using my phone as a cyclometer. The only breaks in the tracking I get is when I pause the ride and then forget to start it back up again, and that's my fault.

You might try doing a full factory reset on the phone. Sometimes those software updates aren't applied right, but fully resetting the phone fixes the problem.

Can't comment on the other thing unfortunately as I have no experience with an external gps since I always use my phone.

Neither have I, at least as far as I'm aware of. It's just that the signal my phone gets is sub-par, which is a different thing from not being there at all.

I find my Samsung Galaxy S5 sport nearly useless for bike use. I've run out of battery with just a few hours of navigating, keeping it in a jersey pocket and only pulling it out to turn on the GPS and ridewithgps when my printed cue sheet/Edge 500 course proved ambiguous. Outside low power mode my dynamo front hub and USB-Werk can barely keep it charged, with it shifting in and out of charge with the screen waking up as speed varies.

It shouldn't be that screwed up. Most of the time the CPU should be sleeping with applications so with GPS/WiFi/bluetooth off it gets the days of battery life available in ultra low power mode (phone and text only, black and white screen, low brightness) except when the screen is on.

If I have my cell phone (an LG G3) in a side pocket on my bag on my bike rack, that's how my traces look as well. Sometimes I'll put it in a handlebar mount for cell phones and it tracks a lot better. I've thought about going the dedicated GPS enabled cycle-computer, but the few times I've borrowed a friend's Edge 810, the results were about the same as with my cell phone up on the handlebars. Since the performance was pretty similar, I figured I didn't need the added expense.

Since your phone's GPS and tracking app used to work fine the problem is not the phone, it must be something that happened when you loaded the new OS. Someone else suggested you do a factory reboot. If you do that just make sure that in the "backup & reset " setting you have all of boxes checked so you don't lose any apps or other privately stored information. If that doesn't resolve the issue than likely the problem was with the app or with the GPS function of the phone. You might need to delete the app that gave you the problem and then reload it from Google play. My bet is that reloading the app will solve the issue but there might be a problem with the phone's GPS function.

On the android phone I owned before the one I have now I noticed one day that for some reason the GPS on my phone wasn't tracking my position as usual. I don't know or recall why this happened but it did. To fix the GPS/tracking issue I had downloaded an app from Google play that was designed to reset the GPS receivers and to fix the issue. Can't remember what app it was now as I have a new phone but whatever it was it worked like a charm and I never had a GPS tracking issue again.

Anyway, I've never tried to use my phone for tracking my rides and then saving them. Likely I'll try that this year at some point just for the hell of it but my current phone ( droid maxx ) and navigation apps ( Locus Pro and Cuesheet ) work very well for general navigation of planned routes. The Droid Maxx came with a bigger battery so unless I'm doing marathons I have no run time issues.

All electronic devices can have problems. At least with smart phones there is a lot of information on the net to help you when it comes to fixing those problems. All devices and/or apps can crash as well so there is always the possibility of having to reboot a device ( or app ) when on a ride. Stuff happens.

Yeah, I hate that the screen ( on android phones ) wakes up whenever the phone senses a change in ( external ) charge voltage. There should be a way to disable that, I just never looked into it myself. When I use my phone for navigation ( planned route ) I'll usually only turn the screen on when approaching a planned turn or if I just want to see the map for a moment. If the app is just running in the background ( screen off ) I'll usually get pretty good run times. ( Droid Maxx with a good size battery )

*Perhaps a work-around for your USB-Werk would be to plug it into a separate ( two cell ) phone charger and then plug the previously charged phone charger into the S5 ( ?)...I figure that way the Werk will help keep the external battery charged and the phone will only sense the voltage on the external battery. Of course at some point the the external battery will deplete and once again you are back to square one. Yeah, I know; you shouldn't need an extra battery if you are using a dynamo charging system but from from what I understand a dynamo can only supply a max of about 800ma of current. Not sure how much current is used when a phone is using an app but unless you are pounding the pedals I doubt that you can maintain that 800ma long enough to keep the batteries charged when using the phone to run an app.

( *Actually, this idea might not work. If using a typical phone battery charger you might have to bypass the USB input charging circuit in order for the varied current from the Werks to reach the batteries. I don't own a Werks so I can't tell you *shrugs*.

The topic was GPS accuracy and reliability. The S5 works great in this regard for me, better than the two Garmins I have. Agree the downside is limited battery life, which I found to be an issue with all the smart phones I've had...maybe two hours navigating with the screen on. For this reason, and a few others, I use the Garmins for cycling even though their GPS is inferior to the S5.

Doze as implemented on stock android only kicks in if the phone is physically stationary for 2 hours. That is its timeout period. If the phone moves, the timeout restarts.

Whatever your phone issue is, doze shouldn't have much to do with it.

I have a Garmin Edge 200, and the GPS sensitivity is quite poor compared with my old iphone 4 and new iphone 6S. It might be that my Garmin is defective, but it's the only Garmin bike gadget I've used.

+1

Interesting, I was almost certain it was doze since it seemed like the phone went to sleep and GPS stopped, albeit after just 10 min or so. Take a look at this graph below. I was doing some repeats on a hill and woke up the screen at the top of the climb. It seems like the phone goes back to sleep after about the same time over and over.

Went back thru the posts but couldn't find it. Exactly what phone model do you have and which version of Marshmallow is it running?