A new Microsoft Bing search app is set to be launched today for the iPhone. The move by the maker of the Windows Mobile OS highlights the concern that Microsoft has for Google search and was inevitable claim analysts.Features of the new search app are detailed in a Bing blog posted by Microsoft employees. They include driving directions, voice search, maps and a “locate me” feature.

The new Bing voice search feature will compete with Google’s voice search for the iPhone, which is seen by many as “pretty good”, so it should be fun to see how the two technologies compare on the device.

The home page of the Bing iPhone app will show a different image every day with clickable, embedded hotspots. A Microsoft representative confirms via email that the app home page will, in fact, show the same image as the Bing web home page every day.

Earlier today, new numbers from comScore Networks showed Microsoft’s search engine topping 10 per cent market share in the United States for the first time in more than two years. However, that growth came primarily at the expense of Yahoo, rather than Google, which saw its market share grow slightly larger, to 65.6 per cent.