I think three devices is a little archaic. I haven't used a dedicated "MP3 player" since 2006.
I also take my training very seriously and it's important to track your progress. Using a notepad for such a task is asking for trouble. Notepads get lost, forgotten, misplaced and are low on the "carry everywhere" priority list. You think carrying around a smartphone in the gym is annoying? I'd rather strap a Note 2 to my chest like Iron Man's arc reactor than carry around a 3"x3" notepad everywhere I go.
Smartphone apps literally revolutionize your work outs. You can track your heart rate, stay on pace to run a 5k in 25 minutes in a 9 week program, have an automatic timer that warns you when your cool down is over, have access to thousands of different work outs. You can mount it to your rode bike bars and use it as a GPS. It'll warn you about changing weather conditions when you're on a hike. You can read a book while you're on any of the cardio machines warming up.
Choosing not to use one, doesn't make you a more credible athlete. There's professional fighters that train 48 hours a week that use smartphones in the gym.
I was thinking of a "universal sports strap" for the Note 2 so maybe you can move it around as you change workouts.
I really wish Apple would release a damn 4.5-5" phone already. If only the S3 wasn't outdated.