TripleA - TripleA is a free (under GPL) turn based strategy game based on Axis & Allies board game.
Invision - Prototyping and collaboration for design teams
Heat Pad - Heat Pad – Relaxing Heat Sensitive Surface is a beautiful app that simulates multiple heat-sensitive surfaces reacting to the heat of your fingertips.
Proto.io - Create fully-interactive high-fidelity prototypes in minutes that look and work exactly like your app should. Sign up for a free 15-day trial and get started.
Particlescape - Particlescape app lets you create stunning patterns at your fingertips.
Balsamiq - Balsamiq. Rapid, effective and fun wireframing software.