Can iPhone 4S use Bluetooth and Bluetooth Low Energy channels simultaneously?
Yes, I can confrim it by doing some test. I have do the below experiment, after connect the bluetooth ear to play music, then open app BLE Utility on iphone4s, hit scan with BT2.0 device and BT4.0 device, which can find BT4.0 device on same time.
Though BT4.0 and 2.0 have physical difference, I think dual-mode BLE can work with two mode on same time by integrate those two parts into one.