Bike Computer or Phone? When a Dedicated Cycling Computer Is Worth It

For short rides, a phone works well. The differences appear on long days, in bad weather and when you need the phone for something else. The table compares published figures for recent iPhones and Garmin's Edge 1050 as an example of a dedicated unit.

Screen-on navigation drains a phone faster than ordinary use, and a ride app competes with everything else on it. Running low on a long ride also leaves you with less battery for a call home.

Apple says iPhone is designed for ambient temperatures between 32° and 95°F (0° to 35°C) and may change its behavior to regulate temperature outside that range. A phone mounted on the bars on a hot, sunny day can reach that limit. Garmin lists the Edge 1050's operating range as -4° to 140°F.

If you follow routes, train with structured workouts, or use heart-rate or power sensors, a dedicated computer keeps those on one screen without depending on your phone. If you plan to stay with a phone, check that your ride app supports your sensors before buying any.

Some features on a bike computer still rely on your phone. On the Edge 1050, GroupRide messaging, Garmin Pay and live features need a paired phone with the Garmin Connect app.

A large screen like the Edge 1050's 3.5-inch display is easier to read at a glance, but it takes more handlebar space and costs more. Garmin's smaller Edge 850 offers much of the same software in a compact unit, and Wahoo's ELEMNT BOLT V3 is a compact option outside Garmin's ecosystem. Our Edge 1050 review links to both.

Basic bike computers measure speed from the wheel: a magnet on the wheel passes a sensor mounted beside it once per turn. On wired models, such as the ones CatEye lists under "Wired Computers" (Velo 7, Velo 9 and Enduro), that sensor is connected to the computer by a wire. On wireless models, such as CatEye's Velo Wireless, the sensor sends the signal without a cable and needs its own CR2032 coin cell.

The practical differences are setup and batteries. A wired computer has a cable to route along the fork, but only one battery: CatEye rates the Velo 7's at about three years at an hour a day. A wireless one is tidier to fit but has two batteries to keep an eye on; CatEye rates the Velo Wireless computer's at about a year.

Both types only know what the wheel tells them: speed, distance and time. GPS computers like the Edge 1050 add maps, routes and ride recording, and connect to sensors wirelessly.

• Worth buying: you ride several hours at a time, follow routes, train with sensors or ride in hot, wet or cold conditions.
• Skip it if your rides are short and you only want speed, distance and time.
• What you have may be enough: a secure phone mount and a ride app cover casual riding. If you already own a fitness watch that records rides, that may cover it too.