As we’ve already mentioned, lower end GPS devices will have the ability to record where you’re riding, and key data, so you can upload it to your computer to take a look at post-ride. However, the more exalted units will have on-screen maps and even turn-by-turn navigation.
On-screen mapping is a pretty useful feature. The ability to glance down and see roughly where you are is vastly underestimated and can occasionally be really useful – for example if you’re on an unfamiliar mountain descent you can have a look down on the straights to see how tight the upcoming corners are. Definitely better than barreling into a blind corner far too quickly. Similarly, if you’re riding to somewhere, as opposed to riding a loop, it can give you a general idea of whether you’re heading in the right direction.
Turn-by-turn is the next level up, but unless you do a lot of riding in unfamiliar areas you may think this is a step too far. It’s really useful if you’re somewhere new or riding in another country (and with the ability to install open source maps on most of them you can map wherever you’re going for free) and a feature such as Garmin’s ‘back to start’ that’ll navigate you back to the beginning of the ride can be a real day saver if you’re out for an explore and end up somewhere unfamiliar.
Again, it’s a case of considering what you want the computer to do. Take Garmin as an example. If you’re a data hound then the Edge 510 will give you more number than you’ll ever need, and there’s no need to go further up the range. However, if you want detailed maps then you’ll need the Edge 810 or 1000, which give you navigation on top of the aforementioned data.