I created GANTTplanner for everyone who is using Google Calendar to manage their projects. GANTTplanner visualizes your calendar as a simple Gantt chart. The nice thing about that? It enables you to group events and look at them with a unified timeline. It makes it much easier to see what is happening at every stage of your project. You can find dependencies at a glance and discover blockers much faster.
Gantt charts do support different zoom levels (hour-years). Events can directly be added and modified inside the Gantt and it is possible to assign each event a task progress. The result can be shared with other users or be exported to PDF/Image.