LONDON — Forget 3G, mobile TV, GPS and MP3 capability. What users really want in their mobile phones and PDAs is two days’ worth of battery life for active use.

According to a survey from market research group TNS of nearly 7,000 mobile users in 15 countries, over 75 percent of respondents said better battery life is the main feature they want from a future converged device.

Hanis Harun, TNS's global account director, said: "The study shows that there is an appetite among consumers for powerful new applications, particularly those around entertainment media and imaging. However, the research also indicates that consumers now fully realize that such applications require enhanced battery life and increased memory and they are demanding these improvements as a priority.”

After battery life the next most important features for U.S. users were high-resolution camera and video camera (50 percent of respondents), the availability of full versions of Microsoft Office applications on the device (42 percent), and a device with 20 GB of memory (41 percent). Mirroring U.S. sentiments, two days of battery life during active use topped the wish list of key features in 14 of the 15 countries surveyed, the exception being China, where respondents said 20 GBytes of memory was the most important feature.

The survey was conducted among 16 to 49 year olds who also accessed the Internet every week. Other countries included in the study included Australia, Brazil, Germany, Russia, India, France, the U.K. and Japan.

The report suggests 46 percent of mobile phone users send pictures and photos via MMS, and 23 percent of respondents said they send video or audio clips through the messaging service.

Sending photos and pictures via MMS is used most amongst users in Japan (80 percent), France (68 percent), South Korea (66 percent) and U.K. (65 percent). Only 20 percent of U.S. respondents said they send video or audio clips through MMS, placing the U.S. among the lowest users of this technology in the world.

Users in the U.S. are also well behind the curve in using the camera function in their phones where they have one. Only 10 percent of U.S. respondents use their camera phone on a daily basis, and almost 70 percent of users never use a camera phone at all.

In total, 59 percent of camera phone users said they use them at least once a week. Camera phones were used most frequently in France, South Korea and the U.K. with almost a quarter using this function daily.