Sonicable

Fast charging cable finally here for iPhones.
This used to be the realm of Android devices, where a cable  can charge faster simply by telling the device it is connected to a wall outlet and it can draw as much current as it needs.
Some USB(Android) cables or wall charger do not convey that message to the device(phone), hence the device only draws 500mA to charge the battery. This is often very slow these days.

Sonicable I guess worked similarly - in the FAQ, it is mentioned that it WILL NOT speed up charging when using a wall charger but WILL speed things up with using a USB port to charge from a PC or presumably from the USB port from a TV.

In anycase I think most people would just charge from the wall charger - much faster than any USB port can charge.  Hopefully in the future USB 3.1 or newer standards can supply more current (2.1A) for such uses.