According to an article in the Wall Street Journal, smartphone apps are getting more popular. Most of those apps are being used on the iPhone and other iOS devices.

The Journal looked at a Nielsen report that reviewed the number of mobile apps found on smartphones. In August, the average user installed 27 apps, which was an increase from 22 found in December.

Of those, iOS leads the way with 40 apps on each Apple device, compared to 25 for Android smartphones and 14 for those with a Blackberry.

While the games category is still at the top, social networking tools are gaining. Apps for Twitter and Facebook, for example, are becoming more popular.

Of all the iOS devices, iPod touch users download the most apps, according to the survey. Overall, 17.6 million apps are downloaded each day across the iOS landscape which include the iPod touch, iPhone and iPad. The report doesn’t break down the number of apps downloaded by specific device.

Nothing in this report seems surprising. If anything, I’m surprised that the number of apps installed isn’t actually higher. Give it some time, and that number will certainly go up.