What is guerrilla usability testing?
Guerrilla testing (also known as hallway usability testing) is a relatively fast and informal way to test ideas, to get high-level feedback, and potentially uncover user experience problems. It can be done pretty much anywhere: a coffee shop, a shopping center, or on the street.
Why is guerilla testing important?
Guerrilla testing works best as a type of formative testing. This means it's particularly useful when you need to validate assumptions and identify core usability problems at an early stage of the design process.