The Apple Watch Series 3 models look effectively identical to the models that came before them, but they are considerably more powerful internally. This particular model, the Apple Watch Series 3 (Aluminum, GPS, 38 mm) does not have wireless 3G capability, but higher-end models in the series also are capable of being connected to the Internet without a "tethered" iPhone and this line is the first Apple Watch series with that capability (although it only can be used on the same carrier as your iPhone). This "GPS" model is required to be connected to an iPhone 5 or newer for most functionality, but it does add built-in GPS and GLONASS as well as a barometric altimeter and Siri support. Like earlier Apple Watch models, all Apple Watch Series 3 devices are controlled with a "Digital Crown" and a Force Touch capable display. This particular Apple Watch, the Series 3 GPS model in the 38 mm size, features a 272x340 OLED screen with "strengthened, lightweight Ion-X glass" packed in a 7000 series anodized aluminum housing with a composite back and "hard coated optical polymer lenses" that connect to the charger. Battery life is an Apple estimated "up to 18 hours" overall, but more specifically "up to 3 hours" of talk time connected to an iPhone, "up to 10 hours" of audio playback, "up to 10 hours" working out indoors and "up to 5 hours" working out outdoors with GPS.