GPS-enabled bike computers are a serious investment, with premium models costing almost $600. With the advent of GPS smartphone apps, you might be asking yourself, "Should I invest in a dedicated bike computer?"
To help you answer that question, I've broken down bike GPS functionality into several categories, so you can decide whether to use your smartphone or go with a dedicated unit.
Bike GPS units attach securely to your bikes with mounts that are included in your purchase. Garmin's quarter-turn mount is the industry standard, and more and more GPS manufacturers are imitating their secure design.
If you want to mount your smartphone on your handlebars, you'll need to buy a bike mount from companies such as RokForm, Life Proof or Wahoo Fitness. These mounts typically cost between $50 and $100 and include a rugged phone case.
A third option is to buy a product like Wahoo Fitness' RFLKT. This is a small screen that mounts to your handlebars and receives Bluetooth data from your smartphone, which you can keep in your jersey pocket or backpack. Your phone acts as the bike computer and the RFLKT just receives and displays data.
Basic GPS Functionality
GPS-enabled cycling computers use their GPS chips to receive data about your location. This enables them to calculate your speed, distance traveled and more. Some are map-enabled, so they can find your location on a map and give you turn-by-turn directions.
Smartphones also have GPS chips, and can gather the same location data, even in areas where you don't have cellular service.
If you have bike computer apps downloaded on your phone, such as the Wahoo Fitness app, then you'll receive the same basic GPS information shown by a dedicated bike computer. And, if you download a map application, such as NavFree, then you'll have access to the mapping functionality of high-end bike computers.
There are three metrics that bike computers measure through separate sensors: heart rate, pedal cadence and pedal power. Traditionally, they've used a wireless transmission technology called ANT+ to receive data from these sensors.
Most bike GPS units are compatible with ANT+, but smartphones are not. In order to receive ANT+ data on a smartphone, you have to buy an adapter that plugs into the charging port of the smartphone and receives ANT+ signals.
In the past, this has been a big reason to go with a dedicated bike computer. However, Bluetooth has released a technology called Bluetooth Smart that is extremely power-efficient, much like ANT+. This means manufacturers such as Polar are making heart rate, power and cadence sensors that use Bluetooth Smart instead of ANT+. Because almost all newer smartphones are compatible with Bluetooth Smart, sensor compatibility is no longer a roadblock to using a smartphone as a bicycle computer.
Battery life is a major reason to go with a dedicated cycle computer. Most bike GPS units have batteries that last over 12 hours, whereas a smartphone running a GPS app, such as Strava or Wahoo Fitness, will only last four to eight hours. To get the same amount of battery life, you'd need to carry an external battery pack. Of course, if most of your rides are less than six hours long, this might not be an issue for you.
Ease of Use
A well-made bike computer will work in the rain and will be easy to navigate with gloved fingers. Smartphones can be difficult to use in these scenarios, because their touchscreens will not respond in less-than-ideal conditions.
While bike computers are easier to use during your ride, after your ride, you have to plug most of them into a laptop via USB to transfer data to an online training software, such as Strava or Garmin Connect. A phone app can simply automatically upload ride data through its cellular connection.
If you're a casual bike rider, consider using your smartphone as a bike computer, and put that extra money toward more cycling gear.
However, if you're a serious cyclist and take long rides in all weather conditions, it makes sense to invest in a dedicated bike computer because of the longer battery life and all-weather functionality.
If you want to save a little money on your investment, I would recommend that you don't pay extra for features such as maps or turn-by-turn navigation because you can always carry a smartphone with you and turn it on if you get lost. Look for a more basic bike GPS, such as a Garmin Edge 510, a Garmin Edge 500 or an O-Synce Navi2Coach.
These models give you outstanding battery life, all-weather performance and the essential features you'll need to train harder and smarter.