Android users are mostly guys. iPod touch owners are overwhelmingly young. And people who carry iPhones are way more likely to lust after an iPad.

Those are a few of differences that emerged from a opt-in survey of 963 smartphone and iPod touch owners conducted in February by AdMob, the mobile advertising company that Google snapped up in November for $750 million.

In a report issued Thursday morning, AdMob highlights six differences between owners of devices running Apple’s (AAPL) iPhone OS, Google’s (GOOG) Android OS and Palm’s (PALM) WebOS, each nicely illustrated with a color-coded bar chart. See below.

1. Guys and Droids. Maybe it’s the appeal of open source; maybe it was the whiff of homophobia in those Motorola Droid ads. For whatever reason, 73% of Android users are male, compared with 58% of webOS users, 57% of iPhone users and 54% iPod touch users.

2. Kids with iPods.  The iPod touch is a hit with the student crowd, which make sense given that Apple hands them out for free with the purchase of a Mac in its back-to-school promos. Based on the survey, 78% of iPod touch users are younger than 25, compared with 25% of iPhone users and 24% of Android and webOS users.

3. Bring on the apps. iPod touch users love their applications — especially the free ones. They download an average of 12 apps a month, 37% more apps than iPhone and Android users. They also spend a lot more time using them: 100 minutes a day, 25% more time than iPhone and Android users.

4. Paying the piper. When it comes to paid apps, iPhone users lead the pack. Half of them buy at least one paid app a month, compared with 21% of Android users, 24% of webOS users and 35% of iPod touch users.

5. Happy campers. Smartphone owners tend to favor their own brand, but some favor it more than others. 91% of iPhone users and 88% of iPod touch users would recommend their device, compared with 84% of Android users and 69% of webOS users. webOS users are nearly three and a half times more likely to not recommend their device than iPhone OS users.

6. Kindle vs. iPad. Steve Jobs may have been on to something when suggested last month that there was a ready market for the iPad in the 75 million people who already own iPhones or iPod touches. In the AdMob survey, 16% of iPhone users said they intend to purchase an iPad, compared with 11% of webOS users and only 6% of Android users. Nearly as many Android owners favored — or perhaps they already owned — Amazon’s (AMZN) Kindle.

AdMob bills itself as the world’s largest mobile ad network, serving banner and text ads for more than 15,000 mobile sites and apps and gathering data from every ad request, impression and click. This survey was conducted from Feb. 5 to 16 among 963 users — 318 Android, 244 iPhone, 356 iPod touch and 45 webOS. The press release is available here and the pdf here, labeled (inexplicably) as the Jan. 2010 report. Results from a similar survey conducted six months earlier are available here.

See also:

• How Apple and Nokia divvy up the world
• How the Android market grows
• Where in the world are Apple’s 78 million handsets?
• The smartphone wars, one year later

[Follow Philip Elmer-DeWitt on Twitter @philiped]