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<concept xml:lang="en" id="GUID-4F004877-DFDD-5282-B8B6-7F36D892B122"><title>Resource Management Overview</title><prolog><metadata><keywords/></metadata></prolog><conbody><p>The Resource Management collection contains components responsible for controlling device hardware. The components give high-level access to phone resources, such as light and vibration, and provide a notification service for power and memory. </p> <section><title>Description</title> <p>The Resource Management collection contains components which control hardware resources, publish battery and power state information, and provide notification in the event of power and memory emergencies. It is dependent on important components, such as Plug-in Framework, Feature Manager, and CentRep. </p> <ul><li id="GUID-CF4630EE-C873-5D83-89C8-7C037F78FA24"><p>Control of hardware resources: The Hardware Resource Manager provides standard Light, Extended Light and Vibra APIs which allow clients to interrogate and control device hardware resources, such as backlights and vibrators. The Hardware Resource Manager is a server for which device creators can write hardware-specific ECom plug-ins. </p> </li> <li id="GUID-784078DA-9000-52E9-AC04-00FF33039E4E"><p>Battery state and power information: The Hardware Resource Manager uses the Publish and Subscribe (P&amp;S) system to provide up-to-date information on the charging status, battery level and battery state of the device. Any application may subscribe to the appropriate P&amp;S keys to receive updates. </p> </li> <li id="GUID-01769637-801A-50D0-A1DC-7F068305E916"><p>The Power and Memory Notification Service notifies clients that the power is about to be switched off, the system is about to restart or if a low memory situation has occurred. Applications use such notifications to save data, and possibly to close down. It also initializes the final power-down sequence if this is indicated in the shutdown request it receives from UI component. </p> </li> </ul> </section> <section><title>Components</title> <p>The Resource Management collection includes the following components: </p> <ul><li id="GUID-5BF15103-47AD-5A02-AB22-FA600BA9B8B8"><p><xref href="GUID-F2289115-B1F0-595D-AA1C-3E01F08911CA.dita">Hardware Resources Manager</xref>  </p> </li> <li id="GUID-A30123E2-F7F6-55BF-B5E2-5555546F0B97"><p>Power and Memory Notification Service </p> </li> </ul> </section> <section><title>Using Resource Management</title> <p>Application developers can use the APIs of the Hardware Resource Manager to develop device-independent applications that can use and control hardware, and can subscribe to the P&amp;S system to receive information on charging and battery state. </p> <p>Device creators can develop hardware specific plug-ins, using standard interfaces, which allow device independent applications to use and control hardware. </p> </section> </conbody><related-links><link href="GUID-F8C8CE42-E7C9-5AFC-86BC-B78F677F1B05.dita"><linktext>Device Services Guide</linktext> </link> </related-links></concept>