A watch with a touch-sensitive screen operated mobile phone built in could be the latest chronographic must-have this summer. The M500 watchphone, from SMS Technology Australia , even promises a multimedia player inside. The device is currently going through US FCC regulatory approval procedures, according to a report on Wirelessinfo .

The device, which has a tri-band GSM phone squeezed inside, has no microphone or speaker built in. Instead, it uses a plug-in handsfree headset to make and take calls - or alternatively a Bluetooth wirefree headset. The M500 watchphone is an update to a previous non-touchscreen model, the M300.

Measuring a chunky 53.9(h) x 44(w) x 16.3(d) mm, the M500's makers claim it will deliver up to 120 minutes of talktime or 100 hours standby.

Features include a multimedia audio and video player as well as regular calendar, memo and to-do list functions. A stylus is also provided for touchscreen operation.