UXPin
A browser prototyping platform combining components, variables, conditional interactions, comments, and developer handoff.
Why use it
Product and UX teams can reuse a real design system, test multi-screen flows quickly, and reduce drift between mockups and implementation.
Where it fits
Use prototypes and playtests to find core experience problems while they are still cheap to fix.
What to check
Free and advanced-logic allowances are limited; code components need engineering upkeep and output still needs target-device review.