[whatwg] Proposal: "Offline-Capable" Meta Tag and API Indicates Application's Ability to Function Without Network Connection

[Brian Blakely]

*The element:*
<meta name="offline-capable" content="true" />

*Its purpose:*
Trigger a UA-native indication to the user that the current application's
primary and entire collection of features can be used without a network
connection.

*API:*
A simple API in the form of a document.offlineCapable boolean setter/getter
would allow an application to dynamically inform the user when the
application is in an offline-capable state.  For example, a nature
photography app may not be truly offline-capable until all of its graphic
assets have finished downloading.  As such, when the application has
detected its final image has loaded, it will execute document.offlineCapable
= true; and the user will be notified that they will no longer need WiFi to
continue usage.

*Exposition:*
This seems simple, almost superfluous, but it is of staggering importance.
 An "online only" stigma is of greatly growing impedance to the web
platform's reputation as a software platform, and it persists among the vast
majority of users.  The latest versions of all major browsers will support
features like DOM Storage and Application Cache very soon, but these
features are largely ambiguous, even amongst the technically savvy.

In addition to implementation of offline technologies, app authors are
currently individually responsible for informing their users that an app can
be used offline. This is not an adequate solution, and a universal
notification that is UA-native would be far more effective at enhancing
awareness.

Because mere utilization of appcache and localStorage do not always make an
application "offline capable", offering a manual flag to authors allows a UA
to complement, or override, its heuristic detections of this state.

The Web must become known as a full software platform, instead of just a
lite version of the "native" App Store experiences out there.  In order to
do so, its features must be more discoverable by users, and in a
standardized fashion.

Thanks,
-Bri