With comScore’s latest report about mobile apps released, we can now pass along some interesting data. For example, nearly half of those using Facebook’s mobile app (48% to be precise) employ the social network’s app the most, based on the amount of time spent using it. Even more impressive, 80% of Facebook’s user base has the app in their top three based on usage. Facebook, by the way, is the top mobile app judging by the number of unique visitors. YouTube is second followed by Google Search, Google Play and Google Maps.

The 1084 smartphone users surveyed for the report spend an average 68.2 hours a month using apps on their handset, and 29.6 hours using apps on a tablet. As you might expect, those in the 18 to 34-year old demographic use apps much more than those in the older demographics. These “Millennials” average 90.6 hours of app use a month on their phones, and 34.7 hours a month using apps on their tablets. The 18 to 34-year old demographic is more apt to find apps they are interested in from sources outside an app store. This group is the perfect target for app-install ads.

One thing that smartphone users of any age are likely to do is to move the app they use the most, to the home screen. 73% of smartphone users want to be able to quickly open their favorite app; only 10% place their most used app into a folder on a secondary screen. And comScore has discovered that smartphone owners spend 80% of their app-using time with one of their three favorite titles. This explains why writing apps is a hit or miss business.

According to comScore, messaging apps are widely used by the Millennials. In fact, the 18 to 34-year old group loves to use messaging and music apps over all others. Interestingly, one of the fastest growing apps with a year-over-year subscriber growth rate of 651%, is Timehop. The app allows you to see what you were doing on social media on the same date as today, but during a different year. And thanks to the larger screens found on tablets, those streaming YouTube on a slate are spending 90% more time per session watching videos than they did last year. Smartphone users have increased their YouTube session time by 34% year-over-year. Increasingly larger smartphone screens might be the reason why.

The survey also revealed that only 9% of those in the 18 to 34-year old bracket use two hands to hold their smartphone. That figure rises to 34% for those 55-years of age and older. Is arthritis to blame? Here’s a stat for developers to remember: push notifications are just as likely to be rejected as they are to be accepted by users. In fact, more users are willing to share their location than accept a push notification.

Check out some of the graphs and charts related to the survey by clicking on the slideshow below.

source: comScore