App manufacturers who monitor usage patterns among iPhone (News - Alert) and iPad users have discovered that people tend to primarily use their iPhones during the day and their iPads in the evening.

Zite, a magazine app named a Best iPad News App of 2011 by Apple (News - Alert), found that users check the app on their iPhones during the day and very late at night. In the evening, when users have some time to kick back and relax, they check the app using their iPads.

“I was surprised at how clearly the various phases of the day – morning, lunch time, and supper time – fell out of the day,” said Mike Klaas, Zite's director of Technology. “It's almost like a story of what a user is doing as they move from one part of their day to another.”

The findings underscore the importance of creating a different mobile app experience on the smartphone platform and on the tablet platform. Smartphone users, according to a spokesperson from Flipboard, want to check news stories quickly while they are in line at Starbucks. iPad users, on the other hand, are looking for a more leisurely and in-depth experience. “Cover Stories have been an incredibly popular section for the iPhone,” Flipboard (News - Alert) spokesperson Marci McCue said, “because it does have that one-hit notion of, ‘What do I need to check in on right now in line at Starbucks?’”

Flud, another news reader app for both iPhone and iPad, noted a significant drop in articles read when its iPhone app came out. However, founder Bobby Ghoshal stated that the drop indicates that people are using the iPhone app to bookmark articles to read later, when they go home and take out their iPads. The number of sessions per user, Ghoshal notes, is steadily rising.

Additional statistics showed that, in addition to peaking in the evenings, users of iPads tended to log on between 8 a.m. and 3 p.m. on Saturday and Sunday. This seems to further support the theory that the iPad is for kicking back, while the iPhone is for quick skimming.