Exists, was a Kickstarter. Pricy (especially since it’s only 3000mAh, same as the $20 Anker one), but usability-wise it seems pretty ideal. You’re meant to use it as your normal charger at home, so it’s always charged since you’ll have it plugged in daily. With the regular kind, it’s really easy to forget to keep them charged - the batteries drain pretty quickly if you just let it sit there.
Sold out everywhere but apparently should be back in stock shortly.
