1. Performance Testing
Run your app through Lighthouse and WebPageTest. Check Core Web Vitals — LCP, FID, and CLS. If your pages take more than 3 seconds to load, you're losing users before they even see your product.
2. Security Audit
At minimum, verify:
- HTTPS is enforced everywhere
- Authentication flows handle edge cases (expired tokens, rate limiting)
- Input validation exists on both client and server
- Environment variables aren't exposed in client bundles
3. SEO Basics
Even if SEO isn't your primary channel, get the basics right:
- Unique title and meta description on every page
- Proper heading hierarchy (one H1 per page)
- Sitemap and robots.txt
- Open Graph tags for social sharing
4. Error Handling
Users will encounter errors. Make sure:
- API errors return meaningful messages
- The UI shows helpful error states (not blank screens)
- You have error monitoring set up (Sentry, LogRocket, etc.)
5. Mobile Responsiveness
Test on real devices, not just browser dev tools. Check touch targets, font sizes, and scroll behavior. Over 60% of web traffic comes from mobile.
Ship With Confidence
A thorough pre-launch checklist saves you from embarrassing bugs and lost users. Take the time to get it right — your users will thank you.