There's a certain charm to the chunky design of the TomTom Spark Cardio + Music watch. It looks more like a Soviet era throwback than a modern smartwatch, with its utilitarian rubber band, monochrome screen and giant flat button below the display, there to navigate the equally sparse user interface.

But to be fair, the Spark is not really a smartwatch; it is a runner's watch, and its simplicity is a feature. It is designed to let you quickly jump in and out of an activity, be it running, cycling, or workouts at the gym, with as little friction as possible. And that monochrome screen serves a purpose, too. The always-on display makes glancing at your stats fast and easy, and between workouts gives exceptional 10-day battery life.

The Spark has space for over 500 songs, although loading the watch is a slow and clunky experience, requiring a computer. But once done, the device can be paired with Bluetooth headphones for music on the go. Even with Bluetooth streaming and GPS tracking, you should get up to 10-hours running with the Spark. I was unable to confirm this, because the battery lasts longer than my legs and lungs allowed.

The accompanying app has a simple interface, showing your activity and fitness trends, once the Spark gets to know you. It's pretty lacking when up against the Fitbit app, and there's no social layer here, so your motivation will have to be beating your personal best, not competing with friends.

I'm sure the Spark is a great fit for serious runners. Aspirational runners, myself included, are better served with something smaller and cheaper from Fitbit, or a fully functioning smartwatch, like the Apple one.