GPS, use my I-phone maybe?

[Catrin]

There is also an issue with battery life for the iPhone. I tried it last summer and my phone died long before the end of my ride - I was using MapMyRide and it was fully charged before the ride.

[westtexas]

If you have an android phone, you can get the app called MyTracks from Google. I used this when I walked on a regular basis to get a general idea of how fast I was walking and how far. I now use it with my phone tucked away in the little bag under my seat for the same purpose on my bike. It measures change in grade as well and allows you to save your routes. It was free and seems to be pretty reliable. I've also accidentally left it running when I wasn't using it and it didn't seem to adversely affect the battery life of my phone either.

[loopybunny]

I have MapMyRide on my iPhone and the first time it was great. Pretty darn accurate.

The second time I tried to use it I was in an area with a weak GPS and it wouldn't work. I don't know if this would be an issue with a Garmin as well.

[CycleTherapy]

I use RunKeeper on my iPhone. I love it. I love that it saves all the data to a (runKeeper.com) website, so you have history of every activity and your route.

You should know that RunKeeper recommends that you disable your WiFi and Push notifications before you start your activity. Battery life is greatly enhanced. I have done 2-2 1/2 hr rides without losing my battery.

FYI- the iPhone 4/with the OS4 is supposed to have a shorter battery life than the previous 3G/3GS model. I have a 3G and intentionally have not upgraded to the the new OS because of the battery issue.

[Jiffer]

Just had a guy in my club blasting the iPhone on our forum because his wife talked him into getting one because it would do "everything" he needed in one device. He tried using it on a 100 mile ride and lost battery at mile 86 and, because of that, says that iPhones suck.

I told him, "I would not say such things if I were you."

I told him to use a bike computer for a bike computer and the iPhone for everything else on the planet. (My entire family of four has an iPhone each ... not to mention my brother, his wife, my sister, her husband, their daughter and son .... even my 3 and 4 year old niece and nephew have iPhones! They don't have phone service ... just use mom and dad's old iPhones for games. Pretty funny seeing a 3 year old totally iPhone savvy!)

The iPhone 4 has longer battery than the others, but still not sure it's the best option for a 100 mile ride. Guessing that's not what you need it for, but maybe the RunKeeper that CycleTherapy recommended will work for you. I don't typically use a navi while riding, unless I stop to check a turn so I'm not much help. Just love iPhones and had to share the discussion that's going on on my club forum. Hope you figure out a good option.

[Kiwi Stoker]

DH loves his Garmin Edge 705- he uses it on his single and on our tandem.
Loves how he can see the gradient, heart rate, speed etc on the computer against the map of our ride.
He brought his off E-Bay as a factory reconditioned model and it works great- software was all updated and all the bugs repaired- even better than a brand new one from some feedback we heard and heaps cheaper.
It's also waterproof in rain and you don't have to buy a seperate casing to protect it. Also the maps are preloaded or on memory cards, so no need to have an internet plan to access Google maps. Battery life is great as it only goes into map/colour mode when you want it to, so reduces power consumption.

My vote would be to buy the tool that is made to do the job and leave the iPhone for making phone calls on the ride.

[JennK13]

I have a Droid incredible and use worksmart labs cardiotrainer. I use the free app, I've had it on for hikes, walks, snowboarding, and use it weekly for rides. It maps even when I'm out of cell range - the map itself doesn't show at the time I'm hiking, but the little blip that's me does, and as soon as it uploads the map appears. Keeps track of elevation change, average speed, max speed and charts it.
I can also upload my routes to mapmyride, which I do to be able to share with my group riders and for posting routes in advance. I just stick it in a shirt or jacket pocket.
I got DH a Garmin Forerunner 305 for his birthday and he loves it.