Cult of Mac Fitness Handbook The iPhone and Apple Watch are powerful tools for getting fit and losing weight — if you know how to use them. Cult of Mac’s Fitness Handbook will show you — step-by-step — how to get the most out of Apple’s devices. From set-up to advanced options, everything you need to know is in these pages. Author Graham Bower (Cult of Mac’s fitness columnist and the developer of the popular Reps & Sets weightlifting app) used technology to get fit in middle age after a bout with cancer. He knows his stuff.