The research firm polled handset owners in a number of categories, such as operation, battery life, design and features. The results were then compiled into a 1,000 point system and ranked by vendor.
Apple claimed the top spot with a score of 791 out of 1,000. LG came second with 772, followed by Samsung with 759. LG also fared well in the traditional handset category, claiming the top spot with a score of 733.
This is the second customer satisfaction win Apple has picked up in recent weeks, having been singled out for its PC business earlier this month by analyst firm Forrester.
The news also comes as Apple celebrates a milestone in its online App Store service with the billionth software download.
The company hopes that the accolades for the iPhone will continue into the summer, when it plans to launch version 3.0 of the iPhone firmware.
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