This bag is perfect, I love it.
I have used this for day to day errands, hiking, and have worn it while riding my bike.
It is the perfect size for my day planner, cell phone, water bottle and all other small necessities. It will fit a packable jacket and some snacks as well as a couple beers for a hike!
This is super comfortable and sits great. I love that it leaves my hands free to do what I need. I would recommend this to others.