Can iPhone 4S use Bluetooth and Bluetooth Low Energy channels simultaneously? iPhone 4S comes with full support of Bluetooth 4.0, which means it can work in "low energy" mode. As far as I know it's a completely different protocol on the physical level, but on the application level in many ways similar to the classic BT.

My question is, are there separate radio units for BT and BLE, i.e. can iPhone 4S use both channels simultaneously? For example, can you connect an audio device via BT classic and some low energy heart rate monitor at the same time?
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.