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.
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.