It seems that every backpack design in the universe requires you to *take the backpack off of you shoulders* to access absolutely anything in the bag. I live in Chicago and I commute using public transportation. I don't like having to take the bag off of my shoulders to access things like my keys, my phone, or my transit pass. At the L stop, one needs to be able to whip out and stow the phone (with transit app) quickly. Standing in a blizzard, at my back door, it's irritating to have to peel the backpack off over my giant puffy coat, hold it in one hand while I remove my heavy gloves with my teeth, unzip/dig for keys, then unlock my door.
So... my inspirational thought is this-- could you design a backpack which would allow one to access these essential items *without taking the bag off the shoulders*?
I tried on my S19 to imagine how this might work. The one spot on the bag that I could reach (without taking the bag off my shoulders) is the lumbar area in the small of my back. If you added vertical zippers onto the back panel of the bag at this spot (right above point where of the shoulder straps attaches to the bottom of each side), and if you had an o-ring just inside each side zipper, I'd be able to attach my keys (on a long tether) to one o-ring. On the other side, I'd be able to attach an organizer pouch (on a long tether) to hold my phone and/or wallet and/or earpods. I'd be able to reach around, unzip these sides, fish out the tethered essentials, open my door or wave my transit pass, replace them in the pocket, zip it back up, and *never* need to take the bag off my shoulders.
Yes, I know there are other solutions. Currently, I use a third party velcro accessory case to hold my phone (it velcros to the S19 shoulder strap so I can carry my phone in the front). And I know some people solve this problem by carrying a 2nd small bag on their front (a side kick, for example), but I'd love to be able to do it all with one bag.