Trim down or bulk up, run faster, or bike farther—however you work out, the best workout apps help you stay committed to physical fitness. I'm an expert in software and work-related issues, and I have ...

I'm standing on top of Machu Picchu, listening to Lil Wayne and smashing flying spheres with a bat in each hand. The instructor encourages me to look around and take in the beauty around me. The next ...