What are the top Twitter apps on the iPhone? It’s hard to say because the iTunes store doesn’t have a Twitter category (Twitter apps are lumped in under “Social Networking). But AppsFire, the iPhone app sharing service, might have an answer—at least for the early adopter crowd who tend to use AppsFire (i.e. people like you, dear reader). AppsFire looks at apps actually downloaded and kept on people’s iPhones. Based on a sample of 1,500 AppsFire members, the top ten Twitter apps on the iPhone are:

1. TweetDeck
2. Tweetie
3. Twitterific
4. TwitterFon
5. IM+
6. Twitelator Pro
7. Twitterrific Premium
8. iTwitter
9. ShoZu
10. Boxcar

Notice that 7 of the top ten Twitter apps are paid apps. The only free apps are TweetDeck (No. 1), Titterific (No. 3), and TwitterFon (No. 4).

AppsFire also collected some data on what percentage of users download Twitter apps compared to Facebook apps (see slideshow below). While it found a total of 32 different Facebook apps on user’s iPhones, compared to a whopping 102 Twitter apps, more users had a Facebook App on their device.

The No. 1 Facebook app, of course, is the official Facebook app for the iPhone, whereas Twitter does not have any official iPhone app. A full 70 percent of users in the AppsFire sample had the Facebook iPhone app, while only 63 percent had a Twitter app. So much for diversity.

The one thing AppsFire does not know, however, is which apps are actually used more often. You can help answer that by answering the poll below:

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