http://todoist.com/html5

Offline access
With HTML5, Todoist offers full access to your tasks and task management whether you’re online or offline. When you can’t connect to the Internet, Todoist automatically switches to offline mode, enabling you to access and update your projects and tasks. Next time you connect to the web, the remote servers are automatically updated.

其实我之前也把我的书签站的数据存在 localstorage 里面，速度确实得到了大幅度的提升。 但是就是不知道 offline/online 切换以及同步的功能应该怎么去做，只能用本地数据冲掉服务器或者用服务器数据冲掉本地数据。

不知道各位有没有这方面经验？