Yep.so is a free and fast landing page builder that helps people create a landing page in just 15 minutes. The tool provides pre-made templates and analytics dashboards to assess the validity of an idea and target the right audience. It offers different plans including a free plan, a maker plan for testing ideas, and a startup studio plan for efficient learning and refining products. With Yep.so, users can create landing pages without the need for coding or complicated features.