Android N Developer Preview 4 has been released, factory images can be found right here, with the full image OTA files here. The new build number is NPD56N. All the same devices that have been supported in the N Preview to date have factory images up now (along with the Sony Xperia Z3). You can check out Google's summary of what's new here. There's also an official blog post here.
New in DP4
Android N final APIs
Developer Preview 4 includes the final APIs for the upcoming Android N platform. The new API level is 24.
You can now publish apps that use API level 24 to Google Play, in alpha, beta, and production release channels.
One of the promised features of Android N was launcher shortcuts, a way for developers to include additional actions in their app's launcher icon following a certain gesture. There were dynamic shortcuts, pinned shortcuts, and a lot of interesting things for developers to explore that you can read about in Cody's exploration of the feature.
But Launcher Shortcuts are going away. Recode had already reported the rumor that Google was going to delay their introduction, and it turns out that was true. The latest developer documentation explains that Launcher Shortcuts will be deferred to a future version of Android (so not N) and that their APIs will be removed from the Android N API starting with the next developer preview. Read More