A Marker.io alternative that also finds the bugs

Marker.io is a feedback tool: a widget on your site lets clients and testers send a marked-up screenshot with technical details, and it lands in Jira, Trello or another tracker. It is very good at collecting what people notice. UICheck collects feedback the same way, on the live site and on screenshots of every screen size, and adds what a feedback tool can’t: it checks the pages itself, so layout bugs, cut-off text and broken forms are in the same list before a client sees them.

UICheck

Marker.io

Feedback from the live siteUICheck: A Feedback button from one script tag: marked-up picture or screen recording, name, no account; can be hidden and shared by linkMarker.io: Yes, its core feature (widget and browser extension)

Mark-up toolsUICheck: Box, arrow, pen and blurMarker.io: Box, arrow, text, blur and more

Technical detailsUICheck: Browser, system, window size, console errors, failed requests, and the clicks and pages in the minute beforeMarker.io: Yes, plus session replay on higher plans

Your own form fieldsUICheck: Up to 5 questions per project, typed or picked from a listMarker.io: Yes, custom fields

Page speedUICheck: The widget loads 8 seconds after the page, so it never counts towards speed scoresMarker.io: Loads with the page (async)

Finds bugs by itselfUICheck: Yes: overflow, cut-off text, overlaps, spacing, forms, accessibility, on every screen sizeMarker.io: No, people report them

Feedback on every screen sizeUICheck: Comments pinned on phone, tablet and desktop side by sideMarker.io: On the screen the reporter has

Checks the fixUICheck: Before and after of the commented spot on the next checkMarker.io: No

Client sign-offUICheck: Approve each page; a dated recordMarker.io: No

TrackersUICheck: Linear, Jira, GitHub, Worksynk; closing there resolves it hereMarker.io: Jira, Trello, Asana, Linear, GitHub and many more, two-way

Screen recordingUICheck: Up to a minute, recorded by the visitor (Prism)Marker.io: Yes

Session replayUICheck: No: the steps before the report insteadMarker.io: Yes, on higher plans

Based on public information, checked October 2026. Something changed? Tell us and we’ll update it.

Choose Marker.io if

You need a tracker UICheck doesn’t connect to (Trello, Asana, ClickUp, Monday)
You want a full session replay with every report
You only need to collect feedback

Choose UICheck if

You want the bugs found before the client reports them
You review sites on phone, tablet and desktop, not only your own screen
You want comments, sign-off, visual changes, Figma comparison and monitoring in one tool

Or use both

They can sit side by side, but most agencies won’t need both: UICheck covers feedback from clients and visitors and does the checking a feedback tool leaves to people.

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