The latest J.D. Power and Associates Wireless Consumer Smartphone Customer Satisfaction Study, which measured customer satisfaction with conventional mobile phones and 'smartphones' in the USA, put Apple at the top of the smartphone category with 791 points out of 1,000. LG topped the ranking for traditional handsets with 733 points. The research was carried out in the second half of last year, awarding points for operation, operating system/features, physical design and battery function.