Hey Product Hunt! 👋 I'm Ruben, and I've been designing for over two decades.Today I'm launching SpotTheUI, something I've wanted to exist for most of my career. After a decade of designing interfaces and mentoring junior designers, I kept seeing the same pattern. People study color theory, memorize typography rules, and watch hours of Figma tutorials. But when it comes time to look at an actual design and decide if it's good? They freeze. The problem isn't knowledge. It's pattern recognition. The best designers I know didn't get great by reading more books. They got great by looking at thousands of designs and developing an instinct for what works. That instinct is a muscle, and like any muscle, it's built through reps. But there was never a tool specifically designed for those reps. So I built one. SpotTheUI shows you two versions of a design. You pick the better one. It explains why. Each challenge takes about 30 seconds. It's like Duolingo, but for your design eye. What's inside: • 480 hand-crafted A/B challenges (every one designed by hand, no AI fillers) • 12 design principles: contrast, hierarchy, alignment, typography, color, spacing, consistency, proximity, balance, emphasis, proportion, white space • 4 difficulty tiers from Beginner to Expert • Progression tracking with badges Pricing: • FREE: 60 challenges across all 12 principles. No credit card. No catch. • Pro: $9.99 one-time for lifetime access to all 480. No subscriptions ever. I intentionally made the free tier generous because I want people to actually experience the format before deciding if they want more. 60 challenges is enough to genuinely improve your design eye. This took 3 months of late nights to build. Every challenge was hand-crafted to clearly demonstrate a specific principle using realistic UI examples. It's a labor of love from someone who genuinely cares about making designers better. I'd love your feedback, what works, what doesn't, what principles you'd want more of. I'm reading every comment. 🙏

SpotTheUI

Train your design eye with 480 interactive A/B challenges

Train your design eye with 480 interactive A/B challenges