For the fourth consecutive time Apple ranked highest in customer satisfaction among smartphone makers, taking the top spot in J.D. Power and Associates' semi-annual survey, albeit with a tighter margin over Android smarphone makers Motorola and HTC.

Apple scored 800 out of 1,000 possible points, down slightly from past scores but still ahead of its closest rivals, Motorola which scored 791 and HTC with and 781, both of which make smartphones based on Google's Android operating system. Smartphone makers that scored below the industry average of 764 included BlackBerry maker Research in Motion with 737, Samsung at 735, Palm with 726, and beleaguered Nokia bringing up the rear with 711.  

The latest rankings from J.D. Power aren't exactly a referendum on the "Antennagate" controversy that swirled around the iPhone 4.  The 2010 U.S. Wireless Smartphone Customer Satisfaction Study-Volume 2 was based on experiences reported by 6,821 smartphone owners between January and June 2010. The iPhone 4 wasn't released until June 24, so had negligible impact on the results.

The firestorm over potential reception problems with the iPhone 4's new antenna, which are apparently alleviated by using a case was stoked by Consumer Reports magazine which said that it could not recommend the new model due to the antenna issue in July. After Apple announced it would halt the free case program it launched to ease the controversy at the end of this month, Consumer Reports reiterated its "not recommended" rating.

The results of the closely watched J.D. Power smartphone study comes on the heels of Apple's top showing in customer satisfaction among PC users in the annual American Customer Satisfaction Index (ACSI) rankings , in the highest rating ever given to a PC manufacturer.

In the J.D. Power study, the iPhone earned perfect scores in five of the six categories: Ease of Operation, Operating System, Physical Design and Handset Features as well as Overall Satisfaction. Yet it scored poorly on Battery Function, which is reportedly much improved on the iPhone 4.

The J.D. Power study also found that mobile applications continue to enhance the smartphone user experience, with two-thirds of users reporting that they download third-party games, while 54 percent say they download travel software, such as maps and weather applications. More than Forty-one percent say they download utility applications, while 36 percent say they download business-specific programs. This indicates that smartphone owners are continuing to integrate their device usage into both their business and personal lives, said J. D. Power in a statement.

Yet another recent study by the Pew Internet Project that found that only two-thirds of cellphone users who have apps on their phones actually use them.

The J.D. Power study also examines operating systems commonly used in wireless smartphones. Among operating systems measured, Google's Android operating platform. Apple's iOS and Palm's Web OS platform perform particularly well, the company said.