Apple's iPhone excelled in the latest American Customer Satisfaction Index (http://www.theacsi.org). However, overall customer satisfaction with the cell phone industry (part of the manufacturing/durable goods sector) slips 1.3% to 74 (out of 100), while wireless service drops 1.4% to 70.

For many users, the advent of smartphone technology has dramatically changed what they look for in a cell phone device.. Two smartphones makers, Apple and Research in Motion (RIM), enter the ACSI with very different results. At 83, Apple (iPhone) leads the field by a long shot, while RIM (Blackberry) lags behind as the least satisfying at 69.

"Companies with weak customer satisfaction often have weak stock performance," says Claes Fornell, ACSI founder. "RIM’s sales are slumping amid a bevy of problems, from hardware and software issues to server lapses that have caused email and messaging outages. Over the past year, share price for RIM has virtually collapsed."

At 83, Apple’s iPhone is a game changer when it comes to customer satisfaction, he adds. No other cell phone company has ever broken into the 80s. Apple’s nearest competitors this year are three companies tied at 75: Nokia (+3%) and ACSI newcomers LG and HTC.

Motorola declines 5% to 73 and ties the aggregate of smaller manufacturers (-1%). This may be unwelcome news for Google as it hopes to make the most of its Motorola acquisition and widen the user base for its Android operating system. Samsung, another company that relies heavily on Android, backtracks 4% to a below-average score of 71.

On the service side, the aggregation of smaller carriers (such as TracFone and U.S. Cellular) maintains a strong lead at 76, despite a small downturn (-1%). All companies show modest ACSI declines except for AT&T Mobility. Last year, customer satisfaction for AT&T and T-Mobile tumbled amid merger talks. This year, AT&T recoups its loss (+5%), but only to tie T-Mobile (-1%) at 69. On the other hand, AT&T is now close to rival Verizon (-3% to 70), whose score has dwindled over three years. At 71, Sprint Nextel nominally grabs first place among the big carriers and holds nearly steady (-1%) following three years of swift ACSI progress (up from 56 in 2008).

The American Customer Satisfaction Index (ACSI) is a national economic indicator of customer evaluations of the quality of products and services available to household consumers in the United States. The ACSI uses data from interviews with roughly 70,000 customers annually as inputs to an econometric model for measuring customer satisfaction with more than 225 companies in 47 industries and 10 economic sectors, as well as over 100 services, programs, and websites of federal government agencies.