Is GWT necessary for my app?

[Mohamed Turki]

Hello GWT experts out there,

I'm learning GAE/GWT to build an application where users can create projects and share their source code, documentation, assign tasks to every participant who must respect the project's schedule etc.

I'm having a hard time learning GWT but i really want to use it for this project to create a nice GUI  (on the other hand, the official tutorial of GAE was enough for me to grasp its basic concepts). My question is, do you think that such an app (like the one i'm building) doesn't require GWT and i could still do well without it? (btw, I'm no expert in JavaScript and I never done anything AJAX before).

Second thing is, I'm planning to use the Google Documents List API and the Google Calendar API for sharing documentation and scheduling tasks for participants, do you think that's even possible or a good idea? (I have no idea how to use those APIs i just want to learn them and integrate them in my app if that's possible ! )