Workout-centric apps like Nike Training Club can help you refine your gym routine. There's one main problem, though: they typically ask you to stare at your phone, which can disrupt your flow and waste time between sets. Nike, at least, knows it can do better. It's releasing a version of its Training Club app for the Apple Watch with the aim of keeping your focus on the workout, rather than reaching for your handset. You have to start a workout on your iPhone, but after that you can concentrate on getting fit.