A smartwatch is a wearable computer in the form of a wristwatch; modern smartwatches provide a local touchscreen interface for daily use, while an associated smartphone app provides for management and telemetry (such as long-term biomonitoring). While early models could perform basic tasks, such as calculations, digital time telling, translations, and game-playing, 2010s smartwatches have more general functionality closer to smartphones, including mobile apps, a mobile operating system and Bluetooth connectivity. Some smartwatches function as portable media players, with FM radio and playback of digital audio and video files via a Bluetooth or USB headset. Some models, called 'watch phones' (or vice versa), have complete functionality of a typical smartphone using LTE technology.
The Fitbit Ionic works fine as a Fitbit tracker, but despite being more expensive than our picks or the Apple Watch Series 1, it lacks many smartwatch functions you’d hope to have. It passes notifications from your phone to the watch, but you can only respond to some of them (with only five quick reply lines); and dismissing them (either one by one or as a group) involves annoyingly hard presses and long scrolls. Syncing music files and offline Pandora playlists requires you to use a desktop app, which is laborious. Two Wirecutter writers who tested the Ionic also had trouble setting it up to work with their Android phones (a 2015 Moto X Pure and a 2016 Samsung Galaxy S7) and had to perform significant troubleshooting to get their data to sync. The Ionic’s battery life, even while using GPS for outdoor exercise tracking, is its most impressive feature, lasting at least five days in one test and nearly seven days in another. The Ionic is most useful to Fitbit enthusiasts who want to track outdoor exercise without bringing a phone; it’s not a good option if you’re looking to deal with incoming information.
Our top pick for most people is the Apple Watch Series 4 with GPS (starting at $399), which has a huge display, ultra-fast processor, Raise to Speak Siri, fall detection and a built-in electrical heart rate sensor for taking on-the-go electrocardiograms. It also runs watchOS 5, which makes the watch even more useful with automatic workout-tracking, offline podcast playback and a Walkie-Talkie voice chat feature.