# Physical button or QR code: what each intercom asks of the visitor > A QR intercom asks the visitor for a phone with a camera and internet; a physical button asks for nothing. What happened when a building's QR went viral, what quishing is, and when each system makes sense. - Published: 2026-07-20 - Canonical (HTML): https://doorlink.com.ar/en/blog/boton-fisico-vs-porteros-qr - Versión en español: https://doorlink.com.ar/blog/boton-fisico-vs-porteros-qr.md --- Smart intercoms are almost always compared on price and app features. There's a prior question almost nobody asks: what does the person standing at the door have to do — and have to own? That's where QR systems and physical-button systems truly part ways, and the difference doesn't show up in any brochure. ## What does the visitor need in each system? With a physical button, nothing. The delivery rider with full hands, a guest from another generation, a kid coming home from school: they all press the apartment's button, the way it's always been done. No phone, no data, no need to know what system the building runs. With a QR intercom, the visitor needs a smartphone with a camera, an internet connection at that moment, and the willingness to scan a code just to ring a doorbell. For a user with data and the habit, it's ten seconds. For everyone else, it's a barrier: on Tappbell's and Bellify's sites (checked July 20, 2026) we found no documented alternative for a visitor who has no phone or ran out of data. With the physical doorbell removed, that visitor has no way to announce themselves, short of the time-honored shout of "hey, throw me the keys!" It's not an edge case. It's the courier, the gas technician in a hurry, the tourist without local data. A building's door is used by people you didn't choose and didn't train; the less you ask of them, the better it works. ## What happened when a building's QR went viral? In November 2025 an X user posted a photo of the front of an Argentine building that had replaced its doorbells with a QR code, [inviting his followers to scan it](https://x.com/ted_duhart/status/1993685656841633971) and play "international ding-dong-ditch": ringing the neighbors' doorbells from anywhere in the world. The post passed five million views, and the quote-posts confirmed, amid the laughter, that it worked. The incident is funny right up until the building is yours. And it exposes the structural difference between the two approaches: a physical button demands physical presence (pranking requires standing at the door, in plain sight), while a QR posted on the street is an internet address. Anyone holding the photo can ring, from wherever they are — and a photo of a building's entrance is no secret: it's on Google Street View, in the neighbors' stories, in a stranger's post. Vendors aren't blind to this. Tappbell, for example, validates by geolocation that the caller is actually near the door. That's a real mitigation and it speaks well of them; it's also one more layer of software that has to work, stay updated and stay bug-free, to win back a property the physical button gets for free: only the person standing there can ring. ## Can a QR code be faked? Yes, and the attack is so cheap it has a name: quishing. It consists of printing your own code on an adhesive sticker and pasting it over the original. It's documented on parking meters in the United States (Austin, Houston, and New York's ParkNYC meters in June 2025, redirecting to fake payment pages) and on restaurant menus; the [FBI has issued specific alerts](https://www.ic3.gov/PSA/2025/PSA250731) about fraud initiated through QR codes, and according to Catalonia's data-protection authority, [78% of QR attacks happen in unsupervised spaces](https://www.apd.cat/en/data-protection/78-of-qr-attacks-occur-in-unsupervised-spaces-such-as-parking-meters-or-charging-points_5624_102.html) like parking meters or charging points. Let's be precise: we found no documented case of this attack on a QR intercom. It's an analogy, not a track record. But a building's entrance is exactly an "unsupervised space" with a stream of people who trust whatever's stuck to the wall, and a visitor has no way to tell a legitimate QR from a sticker pasted on top. A panel of buttons has no version you can counterfeit with a printer. ## And if the internet goes down? Here both smart systems have a limit, but they fall back to very different states. ![Comparison with the internet down: on a QR intercom the visitor can't call and there is no indoor handset; on a retrofit the physical button still rings the handset, and only answering from the phone is lost until the internet returns](https://doorlink.com.ar/blog/sin-internet-en.svg) On a QR intercom, the page the code opens won't load: the visitor can't ring, and since the indoor handsets were removed, no alternative path remains. On a retrofit, the app loses its route too (no software can save that), but the street button keeps ringing each apartment's handset, because that circuit doesn't pass through the internet. The system falls back to what the building already knew, not to zero. ## When does a QR intercom make sense? There are cases where QR is the right answer, and they deserve to be stated just as plainly. If the street panel was stolen or destroyed, there's nothing left to preserve: a QR installs in days, with almost no work, and costs a fraction of any alternative (Bellify lists equipment from ~ARS 117,810, checked July 20, 2026). It's no accident these systems were born in Buenos Aires as an answer to the theft of bronze fronts. Same if the building has no usable wiring, or needs a stopgap while the association decides something definitive. The math changes when the panel is healthy and working. There, replacing buttons anyone knows how to use with a code that demands a smartphone from the visitor trades a maintenance problem for an access problem. [Smart intercoms in Argentina](https://doorlink.com.ar/en/blog/porteros-inteligentes-argentina) has the full three-family comparison, with prices. ## Where does DoorLink land in this comparison? DoorLink starts from one conviction: the modernization should live on the resident's side, not the visitor's. So the retrofit keeps the panel and the physical button (the street changes nothing, in looks or in use) and moves what's new to the neighbors' phones, with an app answered [like a WhatsApp video call](https://doorlink.com.ar/en/blog/como-funciona-portero-inteligente) that we tested with older users who had never used this kind of app. The indoor handsets keep working for whoever prefers no smartphone, and for the cases where neither handset nor app fits, we're developing internet-connected indoor phones that answer like a traditional handset. The visitor, meanwhile, never even learns the building was modernized. They press the same button as always. To us, that's what a well-solved intercom looks like: all the intelligence inside, zero demands outside.