Detect elements that overflow the width of your page across different device sizes.
Find potential spelling errors on your page.
Get a list of all accessibility issues with the reference to the WCAG (Web Content Accessibility Guidelines).
Above Fold Screenshots
Get a screenshot above the fold of your webpage across various device sizes to catch visual errors instantly.
Errors on Multiple Pages
Webapp.io does a deep crawl for other links on your website, and gives you a report for each one.