Another useful feature is multipoint support, enabling it to be simultaneously connected to two phones. The idea behind this is that you can use it with both a personal and business mobile at the same time, or with your mobile and another device like your computer for VoIP calls.
Thanks to support for the Bluetooth hands free and headset protocols all the usual call handling features are available, but the headset isn't compatible with A2DP so you can't use it to listen to the footy results via your phone's radio, for example. It's not exactly a killer omission on a mono headset, but we're pointing it out because there are other models on the market that have this feature.
When it comes to controls the H15 isn't exactly laden down with them. In fact there are only two: a large multi-function button (MFB) and a rocker volume switch. Of course, because the flip-out boom also acts an on/off switch you could also add it to the list if you really wanted to.
Most call functions are handled by the MFB. A single tap is used for setting up calls, answering calls or dropping calls. To reject an incoming call you hold down one of the volume buttons until you hear a tone in your ear, and to mute and un-mute the mic you press both volume buttons at the same time. As you increase or decrease the volume you'll hear ascending or descending notes from ear piece so you know whether you're pressing the right button.
It's all pretty standard stuff and relatively easy to remember, although the call function controls for the second connected handset are more complicated and take a while to embed themselves in your brain as they involve multiple button presses. For example, to voice dial with the secondary phone you have to tap the MFB and then hit one of the volume buttons until you hear a tone.