iPhone, iPod touch users power Apple's word-of-mouth momentum

Ninety-one percent of iPhone users would recommend Apple's flagship mobile device to a friend or colleague and 88 percent would recommend the iPod touch, according to data from mobile ad network AdMob.

AdMob's January data illustrates the power of word-of-mouth marketing for Apple. The Admob data also illustrates some of Apple's halo effect. For instance, 16 percent of iPhone users plan on purchasing an iPad. Twenty-four percent of iPod touch users plan on buying an iPad.

While Apple's word-of-mouth marketing is powerful, Android isn't too shabby. Eight-four percent of Android users would recommend that platform to friends or colleagues. As for Palm's WebOS, 69 percent of users would recommend it.

Here's a look at the money slides from the January AdMob report:

Now there is a flip side to this equation. AT&T is riding along with the iPhone word of mouth. The problem: When it comes to app and data usage, AT&T is becoming dependent on Apple. Verizon Wireless has diversified, but is becoming dependent on the Droid from Motorola.

Consider the January 2010 smartphone manufacturer chart from AdMob. The data illustrates that the iPhone is driving roughly 75 percent of requests on AT&T's network:

In April, AT&T's iPhone dependence was still there, but under the 70 percent mark. The big change from January 2010 from April 2009 can be seen in Verizon Wireless usage. In April 2009, Verizon Wireless was highly dependent on Research in Motion via the Storm. In January, Motorola and HTC were the big devices in the Verizon portfolio. That's the Android effect at work.

Here's April's AdMob data: