DeWalt is more of a perfectionist then an innovator. Let me clarify, they have some really innovative products like the Gyro screwdriver. However generally they are not the first to plate with new innovative products like competitors such as Milwaukee tool. Milwaukee has had it's 12v power source out for a while now. The DCB090 does one thing and one thing only. It provides you a reliable and safe USB power supply for all your phones, tablets or anything else that uses a standard 5V USB plug. USB plugs have been around for years and have proven their ability to be a reliable connector for electronic charging needs.
The unit for some reason reminds me of a sea shell. It simply slides on top of any DeWALT 20V or 12V MAX battery. Obviously you will get more run time with an 20V XR 4.0 battery than you would 12V Max battery. I was able to charge my iPad quite a few times on one XR battery. I even charged my phone a few times on the same pack. The unit puts out 1.5 amps of power and will go a little slower when two devices are plugged in. Tablets will take a bit longer than phones to charge in our tests.
Since the DeWALT 12V MAX batteries lack a fuel status gauge the DCB090 has one on-board that will remain lit for a few seconds to give you a reading. To check the status again you will have to slide off the battery pack and reinsert it. If you have a smart phone and are out in the field a lot the DCB090 is a no brainer. It will keep your equipment charged and powered all day. You can throw a 12v MAX on charge for 20 min and head out the door knowing you have a few phone charges on hand or grab a 20V XR for multiple devices all day power.