The iPhone 6s has been mostly a dream of a device, due mainly to its practically instantaneous performance that rivals my 15" Retina MacBook Pro in real-world usage. In fact, I only use my Retina MacBook Pro when I need to multitask more efficiently or fill in a gap, such as in web development or Photoshop. We are talking ~ 7-8 hours of usage on the iPhone daily compared to 7-8 hours weekly at the very most lately on the rMBP. For me it's even superior to an iPad because many times throughout the day I'll need to use it one-handed, and I feel the iPad is only worthwhile if a user is going to be sitting for periods at a time. I'd venture to say the Apple Watch is my runner-up. Even though the third-party apps are mostly useless at this point, the watch's hardware and interface sport a luxurious feel; there's a lot of potential here as it feels distinctly futuristic. Based on the current state of Apple, the Watch, iPhone, and iPad are surprisingly easily the future of the company in my opinion.