Do I need a cycle computer if i have an iPhone?

sidneysides

New to MTB here - I have a few cycling apps for the iPhone and there are plenty more available. If I mount my iPhone to the bike, do I need a cycle computer? Are there things that the cycle computer can do that an iPhone can't? (Such as RPM etc). Bike used for commuting and trails?
Thanks

cooldad

Do you need a computer at all?

GHill

Depends what info you want from it (and how accurate).

I start a GPS tracker on my phone, throw it in my Camelbak and then take a look at the stats at the end (distance, average speed, max speed, altitude change). The GPS accuracy isn't brilliant though.

slimboyjim

I use my HTC as a gps unit and it gives me most of the functions of a bike computer. Drawbacks of using your phone is that programs can drain your battery, and if it's mounted to your bike you risk damaging it in an accident.

Why not try out a couple of the cheap programs/trial software and see how you get on. I'm sure if you do a search on iPhone here it'll bring up a wealth of options for which programs are any good...

MountainMonster

I would get one just to be on the safe side. If you use gps on your phone, not only will it not be that accurate to calculate distance as phones are properly built for that, but it will also drain the battery down fast.

It's worth even just buying a really cheap (15pound or so) computer to have,

Steve_F

Can't add much more. Wouldn't want to run the phone on anything less than full battery for more than a few hours in case it was dead if something bad happened. No emergency calls due to running a GPS app would be pretty annoying.

GPS seems good out in the open, marginal in the forest.

VWsurfbum

MountainMonster wrote:

It's worth even just buying a really cheap (15pound or so) computer to have,

This

I use both if i'm going somewhere new but genrally just my cateye jobby

qwerty1982

VWsurfbum wrote:

MountainMonster wrote:

It's worth even just buying a really cheap (15pound or so) computer to have,

This

I use both if i'm going somewhere new but genrally just my cateye jobby

Ditto, my iphone GPS is shite so it says my ave speed can be about 80mph! yeah i wish, so computer it is for me with iphone for fun.

bike-a-swan

cooldad wrote:

Do you need a computer at all?

Agreed. I bought a gps for hiking years back, used to use it on the bike all the time. Eventually realised that basically all I was doing was carrying around extra stuff that was purely for burning batteries.... Speedo hasn't even been on my roadbike in months.

Bar Shaker

The iPhone GPS chip is as good as the app that polls it.

Cyclemeter is rubbish. Motion X is superb, partly because it uses the GPS chip very well and partly because it comes with excellent terrain maps.

I use mine with an external battery and docking lead which gives 6-7 hours running time. I use the phone app for knowing where I am and for tracking my routes, or displaying new routes to follow (you can load up gpx files from someone else's track log). For rides that I know or for short rides, I just use a bike computer.