Apple Watch is a series of smartwatches designed and manufactured by Apple Inc. It connects with iOS and other Apple products and services and includes fitness monitoring, health-wellness features, and wireless connectivity. In April 2015, Apple debuted the first Apple Watch, which immediately became the best-selling wearable device: In the second quarter of fiscal 2015, 4.2 million Apple Watches were sold, and by December 2020, more than 100 million people are expected to own an Apple Watch. With a few exceptions, Apple has announced new generations of the Apple Watch each September, each with enhanced internal components and branded as a 'Series' by Apple. Every Series has been sold in multiple variants defined by the watch casing's material, color, and size (except for the budget watches Series 1 and SE, which are only available in aluminum), and, starting with Series 3, by the option of LTE cellular connectivity in the aluminum variants, which is standard in the other materials. The watch's band can be chosen from a variety of Apple selections, while watch variations in aluminum co-branded with Nike and stainless steel co-branded with Hermès are also available, with special bands, colors, and digital watch faces bearing those brands' logos.