Marvel Teams
We're getting close to testing Marvel teams, this is the modal that appears when you want to add people to a project.
Teams has been one of the biggest challenges for me so far with UX, we've gone for a different type of teams feature and hopefully it'll be 10 times more useful to designers and creatives than anything else out there.
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Marvel is a free (like really free) mobile and web prototyping service for designers, unlimited projects, easy to use and runs off Dropbox. Give it a go