About the same as my Z1 Compact. A few days ago I used GPS Essentials tor record a 70-minute outing and the toll on battery power was 9%. And this phone was old-new stock that was already a year old when I bought it last 13 months ago.

This is going to sound like voodoo, but it isn't: turn on the GPS receiver in your phone, go somewhere with a clear view on a nice day, load up an app that uses location, then leave your phone there for an hour or so. Once your phone gets a lock on a GPS satellite it should download catalog data that contains information on satellite positioning. Some of this data is accurate for months, the finer data is accurate for about 30 minutes (this is why your phone should reacquire a satellite lock fast if the GPS is disabled/enabled within that time period). So, launch Strava on your phone before you start riding so this work isn't happening while you're recording.

This can be easier to do on cell phones, though. Try using this app to calibrate the compass, clear the GPS cache, then download A-GPS data: https://play.google.com/store/apps/d...sim.gpsstatus2 .

The A(ssisted)GPS data should contain the data I mentioned above, skipping some of the work the GPS receiver and software in your phone would have to do to get a satellite fix. If this information is updated and accurate your phone will be able to get a faster fix than if it has to do all that work on its own. I honestly don't know what triggers this refresh on phones and how often it happens normally; I've never gotten a good answer to that.

This morning, using GPS Essentials on my Sony Z1 Compact. My ride was more or less completely flat, and yet it gave me this!

And yet on my riding buddies old Garmin 500, he had to charge his Garmin on a century we did together and I did the entire century without recharging my phone until later that evening. This was almost two years ago when he purchased the Garmin new. He now has an 800 and the battery life on it, while much better, wasn't worth the jump in price from what I have now to a Garmin. I will concede that if you are doing a double century and you don't charge your phone while on the ride, it will die on you. Since I don't do double centuries, I don't have to worry about it. I've never drained my iPhone's battery on any ride of 100 miles or less.

I took a closer look today and found out it was wrong about the phone's GPS performance: it's actually spot on. It turned out that either Google Earth or the KML file as written by GPS Essentials didn't do a very good job plotting the orange line and superimposing it on the map. If I double-click on any of the empty stretches where I think the line is supposed to be, it will still zoom and center the entire track.

That said, nevertheless, it could have been more accurate.

Cell phones don't have altimeters, for the most part, so the elevation data is coming from the GPS and calculated via topography, which is not as accurate as a built in altimeter.

Also, most cell phones don't have an active GPS antenna. You can do that in a dedicated bike computer, since you can sacrifice the space.

You guys are right though, someone should really make a bike computer with modern cell phone GPS components but bike computer sizing