Two of the features I have been really waiting for developers to get their hands on is headless apps and BlackBerry Hub integration. Both of them have been revealed in BlackBerry 10.2 though a few developers have been granted access to them in earlier OS builds. Now BlackBerry is asking developers to apply for access to add this permission to their app if they plan on running in the background for more than 20 seconds. (The application is here) BlackBerry has also detailed some of the limits they have placed on background headless apps that do not have a UI to ensure they do not kill your device performance or battery.
First of all background apps can occupy only 3MB of memory but can allocate more through system permissions. They also have their CPU usage limited to 7-25% when they are running in the background. This usage limit is also based on if the app is in the system, background, stop, or traditional Foreground position. By default a headless app also only runs for 20 seconds and must ask users for the _sys_run_headless permission but longer running apps have to apply to BlackBerry for _sys_headless_nostop permissions. Background apps can no be set to either launch based on push/sms/geofencing or they can just start based on a broadcast trigger like the device booting up or shutting down.