The Apple Watch 42mm (1stgen) was announced in 2014, September. Released 2015, April With 1.65 inches Retina OLED, 450 nits (peak), Powered by Apple S1 (28 nm) and running watchOS 1.0, upgradable to 4.3.2, the device delivered smooth performance and multitasking capabilities. while the Li-Ion 250 mAh (0.94 Wh), non-removable ensured long-lasting usage.