I'd like to let you know about a new app I got submitted for approval on AppWorld, called MockItUp. MockItUp is a wireframing tool designed for tablets, allowing you to build mockups quickly and easily without needing your PC. It is a free app for the time being so, once RIM approves it, you can just download it and give it a go.
In the meantime, here is a short YouTube video depicting MockItUp in action: Wireframing with MockItUp
I'm really looking forward to your ideas on this app and can't wait to share ours with you. Don't be strangers and let me know how good (or bad ) it is. I also plan to add cool new capabilities in the future such as diagramming module to enable Visio like projects, real time collaboration over the local network, theme packs for Playbook, IOS, Windows 8, Android and more.
If you want to stay up-to-speed with what's going on with MockItUp, feel free to follow MockItUp's Facebook