One of the main reasons to consider the LG DoublePlay is its appealing and unusual interface. Pull up the browser and you'll see thumbnail bookmarks for sites you've visited on the second screen. Use the Richnote app and you can create a new memo.
There are nine apps included like the Bobsled group messaging app, music and calendar apps, browser and social apps, and a photo app which all work with the DoublePlay's unique screens. Typically, the top screen displays a typical portion of the interface and extra controls are displayed in the lower screen.
The dual-screen setup is most effective for keeping tabs on things or multitasking. For example, LG includes the Sim City Deluxe game, so you can get engrossed in building a city on your phone but also run the messaging app on the secondary screen to reply to that message your boss sent you.
Unfortunately, this novelty wears thin quickly. The main problem is that there are only nine apps that work with the secondary screen, and there doesn't seem to be a plan to add more.
When you download the Evernote app or Skype, you won't be able to run part of these apps on the second screen and there's no way to find out which apps are supported shy of running each and seeing if the secondary screen does anything.
The confusion is exacerbated by having this blend of widgets and apps placed on the secondary screen. Many of the widgets, including one for social networks and for messaging, plus several others, do not work with the secondary screen once opened.
So, you might run the Friends social network widget and the social network app for the secondary screen, but they do not work in tandem. Oddly, the widget and secondary-screen apps often look alike, even if they do not work in concert.