Add and edit UI wireframes directly from your Google Drive
Balsamiq Mockups for Google Drive allows you to create, edit and share sketch-quality wireframes, all within Drive.
Balsamiq Mockups is the easiest, fastest, most fun, best supported wireframing tool on the Internet. The integration with Google Drive is pretty slick: you can create new mockups directly from the "Create New" menu, or edit wireframes just by clicking on them, all within the browser. You can even collaborate on your wireframes with others, in real time!
When the 30-day fully functional trial expires, you and your collaborators will still be able to open and edit mockups, just not save them. To do so, you have to sign up to either a no-risk $5/month or a $50/year subscription plan. You can stop and restart your subscription at any time, too!