13 December 2010

Manage the application cache in Google Chrome

After the recent launch of the Chrome Web Store, another internal page from ’s browser becomes more useful to the regular Chrome user. Powered by HTML5, some apps can also run offline, by using a local storage separated from the all-purpose browser cache. The page AppCache Internals displays the data stored locally by these HTML5 applications in Chrome and lets users delete the cache individually. It’s address is chrome://appcache-internals/. It can also be accessed from the ‘directory’ of internal pages, which has a much easier to remember address: simply go to about:about and click the first link to open the Appcache page.

Google Chrome AppCache pageA couple of things I noticed about this page:

  • As long as you are online, removing the cache will not impact the functionality of the app, because it will be rebuilt immediately by downloading the files from the Internet. Obviously, while offline removing the cache is similar to removing the app: it will become just a dead link, until you connect again;
  • Emptying the browser cache doesn’t have any effect on the app cache. As far as I can tell, this internal page is the only place you can manage it;
  • There is no ‘Clear all’ button, so removing a large number of offline manifests can quickly become tedious. Ideally, this setting should be added to the regular Clear browsing data… dialog;
  • Uninstalling the app doesn’t automatically remove it’s offline data. This could prove useful if you remove an app, but still use the associated website. On the other hand, if you try out a lot of apps and later decide to uninstall them, all the associated data will linger on your hard drive. This could quickly become a new source of hard-to-identify bloat, like data stored by other plug-ins.
  • You can also use the page to quickly check whether your apps have offline support. A good idea, especially before starting a trip in an area with poor coverage! As you can see in the picture, only two games have stored data offline, although I have more apps installed. Right now, the number of offline-enabled apps is probably pretty low, but hopefully the Chrome Web Store will become popular and encourage more developers to add these function to their web pages.


  1. Nice blog!

    While I'm not much into apps, I did look at 20thingsIlearned to get an HTML5 experience as soon as it was out. I used both Firefox 3.6 and Chrome. The better thing with Firefox was that the local storage was easily identified whereas with Chrome it wasn't. Do compare the two browsers if you get the chance.

  2. Yes, in Firefox you can view and manage the application cache through the standard 'Options' dialog, as explained here: Offline resources in Firefox.