Anything you could open in a browser. Type the address of a public website — yours, a competitor's, a supplier's, one you are about to buy from — and VONWEB visits it the way an ordinary visitor would, then tells you what is wrong with it.
It is a condition report on a website. VONWEB measures the site across six areas — whether it is reachable, how fast it is, its HTTPS certificate, its search visibility, how it behaves on a phone, and the quality of the page itself — and gives you one figure out of a hundred, with every finding behind it written in plain words.
You do not need to own the site, prove anything, or install anything on it. Everything VONWEB reads is what any visitor's browser reads.
If you leave the scheme off, VONWEB assumes https://. Capitals are fine, a trailing
dot is fine, and a link copied out of a browser's address bar — query string and all — is fine. The
part after # is dropped, because a server never sees it.
Why private addresses are refused. VONWEB fetches the page from a server, not from your phone. Letting anyone point that server at a private address would make it a tool for probing networks it has no business in, so private and internal ranges are turned away before anything is fetched — and again on every redirect the site tries to follow.
The address leaves your phone, the survey runs, and about nine seconds later you get the report. Nothing about the survey is kept on the server: no account, no request log, no copy of the result. The report lives on your phone and nowhere else, which is also why your history disappears if you delete the app.
A survey is a snapshot, not a verdict on anyone. It is one moment, from one vantage point, reading public information only. A high figure is not a guarantee and a low one is not an accusation.
A site that is down, expired, refusing connections or timing out is not an error — it is a finding, and a serious one. You still get a report with a figure, and the reason sits at the top of it in plain words. VONWEB only tells you it could not run at all when nothing about the site could be assessed.
More about the six areas and what each one measures is on the main page. The Privacy Policy and Terms of Use are the same documents the app carries, word for word.