There are two options when it comes to tracking your bike rides. You can use your smartphone and an app like Strava or MapMyRide, or opt for a GPS bike computer, which can cost anywhere from $100 (£80, AU$130) all the way up to $600 (£480, AU$800)
For most commuters or recreational riders, the phone may be the better option. If you're serious about biking exercise and maybe one day competing, though, a GPS bike computer is worth the investment. Here's why:
Better battery life
The No. 1 reason to go with a GPS bike computer is for battery life. A smartphone running a GPS app like Strava or MapMyRide may only last a few hours, whereas many bike computers can get up to 16 hours. Commuters may not have this issue, but you don't want to be out on a 60-mile ride and have your phone die.
Most GPS bike computers carry a water-resistant rating of IPX7 and won't be damaged when used in the rain. Unless you own an iPhone 7 or Samsung Galaxy S7, which are both water-resistant, it would be safer to ride with a bike computer.
It can be difficult to see the screen on your phone on a sunny day. You won't have this problem with many bike computers. While they may not be as vibrant as your phone, they do a better job of reflecting sunlight.
Access to more accessories
Eventually you will want to purchase more advanced sensors and accessories for your bike. This includes things like cycling power meters, heart-rate chest straps and speed/cadence sensors. Many of these support both Bluetooth and ANT+ to connect with a bike computer, but there are still some that are exclusive to ANT+.
Now here's the problem. While nearly every smartphone on the market supports Bluetooth, only Samsung and Sony incorporate ANT+ into their smartphones. That means you won't be able to use a handful of accessories when using an iPhone (or another phone) over a bike computer.
While high-end GPS bike computers can be quite expensive, there are more affordable models, such as the Polar M450, available for around $150 (£120, AU$319). The M450 is water-resistant and has 16 hours battery life and a great display, although it doesn't include support for ANT+.
Many cheap smartphone bike mounts can be subpar and may not secure your phone correctly. A quality mount, such as the Quad Lock, could cost you between $50 (£40, AU$65) and $100 (£80, AU$130). You would then have to drop another $25 (£20, AU$35) for a water-resistant cover. Even then, there is still a chance your phone becomes dislodged and could shatter. Why even risk it?