Tests performed by Apple in August 2024 working with preproduction Apple Watch Extremely 2 (GPS + Cellular) paired using an apple iphone; all devices tested with prerelease software package. Battery life varies by use, configuration, cellular network, signal power, and a number of other components; actual final results will range. https://www.jowissa.com/de-na/products/roma-ethno-swiss-womens-watch-j2-024-l