From Nokia Developer Wiki
DOS(DOmestic Server) Client API are useful to access service offered by DOS server. This article demonstrates the use of DOS Client API to get notification when an accessory mode changed(for example accessory is connected or disconnected ), with code example which helps to understand how this API can be used. Note that this API, DOS Client API, is not part of the public SDK. So you have to download it from SDK API Plug-in before using it. Furthermore, the author added a working demo project, which can be used for more detailed study of new opportunities for various kinds of experiments.
Q: What capabilities are needed for the application? Is it possible to make this work with selfsigned apps?