It's easy, fast (as compared with other tools I've used), free! And it has an excellent interface that makes collecting user-generated content simple & painless. There are some features missing - like customizing your own questions/feedback fields - but this can be worked around by creating new question types in their support section. If you want rapid iteration through UX design ideas without having to create something from scratch each time, then give pastel a try. You'll quickly see why soβ¦