That's correct. We went back and forth A LOT on this.
We ended up with the point of view that M8 is a headphone amplifier, not a charging accessory for your phone or tablet. That's a very big philosophical difference.
If M8 was a charger, it would need to provide juice to the iPad while running itself. The problem is - in that case M8 will drain its battery in an effort to help out the iPad. And iPads are hungry! M8 doesn't stand a chance giving up all its available power to the iPad and still working for a long time.
So this is why we made the smart decision -- charge the iPad ONLY when we are connected to the wall. That's when plenty of power is available for all devices. We will gladly charge the iPad and our own battery when running off the wall. But M8 will NOT charge the iPad or iPhone when it is NOT connected to the wall (running off the battery).
We make the assumption that the user is smart and will have a freshly charged battery in the iDevice, such that M8 will not have to be the on-the-go charger.
We believe that this is a good compromise that will allow you to have true 6.5 hour play time on a flight from NY to LA, while each unit is running off of its own battery.
Edited by mgoodman - 8/23/13 at 2:01pm