Mobile analytics company Localytics plotted observed iPhone activity by the hour, adjusted for timezones, and came up with a chart that validates most people’s suspicions: iPhone owners use their apps much more on nights and weekends rather than during the weekday. The obvious conclusion: The iPhone is used much more a personal gadget rather than a professional tool.

Boston-based Localytics gets its data directly from apps that incorporate the company’s analytics tracking tools. The data is, of course, biased by being measured only through a fraction of the 100,000-plus apps in Apple’s store, but Localytics’ analysts believe it’s enough of a cross-section to apply broadly to the rest of the app market.

Weekday usage peaks at 9 PM local time, they found, with Tuesday being the busiest weeknight. There’s an obvious implication: People are using iPhone apps while watching TV. That bodes well for the iPad’s adoption as a couch-surfing device, Localytics exec Brian Suthoff told me in a phone interview. “It seems people are reaching for their iPhone rather than their laptop” on the couch, he said.

On weekends, iPhone owners only increase their app playtime by 7 percent over weekday use, and as shown in the chart, Saturday app usage is spread out surprisingly evenly across the day.

Localytics, founded in 2009, is privately funded.