I would like to write an application which run in the background at all time. Ideally, this application will be running as soon as it is downloaded and installed. Also, when the phone is rebooted (because of low power, for example), the application will be started as soon as the operating system is up and running. This type of application would be similar to a daemon process in Linux or a System-tray application in Windows. I just wonder if the current application framework would allow me to write such an application. Where can I find information on how to write this type of application? Thank you very much.