Why not just use the camera app?
Your phone's camera reads a QR code and offers the link in one motion. That is the right tool when you already trust the code: a menu on the table of a restaurant you chose, a poster in your own office. A scanner app earns its place when the code is somewhere you did not choose, when money or a password is on the other side, or when the code is not a QR code at all.
What the camera does
Many camera apps decode a QR code and show a small chip with a shortened address; tap it and the page opens. The part that matters is often cut off, and the chip disappears when you move the phone. Usually there is no history, so a code you scanned yesterday is gone.
What it does not do
A camera app does not tell you that paypa1.com is not paypal.com, that a short link leads somewhere else, whether the network a Wi-Fi code joins is open, or that a payment address is on a scam or sanctions list. Many camera apps read only QR codes, and they often give up on a code that is torn, faded or printed on a curved surface.
What a scanner should add
Show the address before anything opens, the whole of it a tap away. Check it on the phone: lookalike names, hidden sign-ins, short links followed to where they lead when online lookups are on, open networks, known phishing and scam entries. Say what was checked and what was found, and never say "safe", because no list can promise that. Keep a history you control. Read product and shipping barcodes, not only QR, and keep trying on a damaged code across frames instead of stopping.
When the camera is enough
A code you can vouch for, in a place you chose, leading to a page you expected. Use the camera. For everything else, a scanner that shows the link before it opens costs you one extra look, and that look is the whole point.
Verdetto is that scanner: free, no ads, no accounts, no tracking by Verdetto. The result sheet shows the address, the checks and the result line, and the decision stays with you.
Related: How to check a QR code link · Fake QR codes in the wild