Google has added "sophisticated" voice recognition technology to its search software for the Apple iPhone.

Said to be due to go live through iTunes today, users will be able to speak to the pone to ask the search engine "virtually any" question, such as "Where's the nearest Starbucks?" or "How tall is Mount Everest?"

The sound is converted to a digital file and sent to Google's servers, which determine the words spoken and pass them along to the Google search engine.

The search results are said to take "just seconds" on a fast wireless network will include location aware results.

Yahoo launched its voice-activated oneSearch in the UK this week, that offers voice search for some BlackBerry and Nokia users.