This specification defines an API to provide Web applications with access to various properties of the system which they are running on. Specifically, properties pertaining to the device hardware are addressed. Examples include battery status, current network bandwidth. Additionally, some of those properties offer access to the environment around the device, such as ambient brightness or atmospheric pressure.

Work on this document has been discontinued and it should not be referenced or used as a basis for implementation.

The System Information API was defined to enable API access to a wide variety of information about the user system, including sensor, power, network, interfaces, codec and other information. While working on this specification the Device APIs Working Group decided there would be advantages to working on specifications focused on specific modules, enabling faster specification development, reduced scope of testing as well as the potential for reduced privacy and security attack surfaces. Work on the System Information API specification was discontinued in favor of modular specifications, for example Battery Status API, Ambient Light Events, Proximity Events, and the Vibration API (call for consensus to discontinue work). Note, a Sensor API was considered by the working group but also abandoned for similar reasons.

The Charter of the Device APIs Working Group continues to include this work as "in scope", so the working group could decide to resume work if warranted by new information.