In an effort to stave off the quell of angry iPhone users with dropped calls and slow data connections, it appears that AT&T stepped in to help Apple tweak the device so it used available bandwidth more efficiently.

AppleInsider is reporting on a new piece this week from The Wall Street Journal where AT&T chief technology officer John Donovan explains how he and other executives flew to Cupertino to give Apple “a crash course in wireless networking.” Over the course of “regular return meetings,” the iPhone designers were able to tweak the device to work more efficiently on the telco’s network.

"Apple rejiggered how its phones communicate with AT&T's towers," the report claims. "As a result, the phones now put less of a load on the network for such simple tasks as finding the closest tower or checking for available text messages."

As a result, the exec claims that Apple’s designers are now “in a Master’s class” on networking, having worked with AT&T to make dramatic improvements to the iPhone. Donovan didn’t reveal exactly what was changed or whether the revisions were made to hardware, software or both.

The report also discloses how AT&T execs set up a “100-day play” in December, 2009 in an effort to improve the company’s network in large cities where users experienced the most problem with dropped calls. That work appears to have paid off -- at least with the results of one study released last month which found that AT&T’s 3G network speeds had improved by a whopping 84 percent.

The Wall Street Journal was quick to note, however, that AT&T is still “racing” to improve its network, especially in the shadow of persistent rumors that Apple is working with competitor Verizon Wireless on a CDMA version of the device slated for as early as this year.

It has been widely rumored that AT&T’s exclusive on the iPhone will likely come to a close this year, which Apple likely needs to further continued growth of the handset in the U.S. market.