"I'd like it a bit warmer, but not too much." Anyone who works in a salon knows what that sentence is worth: nothing. The client has one picture in her head, the stylist has another, and the gap only shows up afterwards, in the mirror. With Miraviso I have been working to make that gap visible before you start, on a tablet, with the client still in the chair.

In an earlier article I described the live hair colour try-on, which colours the hair in the camera view and runs entirely on the device. This is something else: a proper consultation, step by step, that starts from a photo of the client and builds the look using the words of the trade.

You talk like in the salon, not like to an app

The tablet does not ask anyone to type. The stylist taps buttons grouped as Cut, Styling, Technique, Tone, Touch-ups and, for those who use it, Colour analysis. Inside are everyday words: balayage, shatush, babylights, airtouch for techniques; shades for colour; and touch-ups like "Warmer", "Cooler" or "Darker roots".

The starting catalogue is already rich (techniques and tones alone add up to more than thirty entries), but every salon adapts it: it can switch off what it does not offer, rename entries to match what it calls them at the chair, and add its own. If your salon calls "honey blonde" something else, the tablet shows it under that name.

There is also a button people really like: "Like the swatch". The stylist points the camera at the swatch from the colour chart that the client picked, and that colour goes into the preview. No trade names to interpret: it is the swatch the client actually touched.

All over or only the strands

This part came from a real test. At the end of September a salon owner used the tablet with real clients and pointed out something I had missed as a developer: the same colour changes everything depending on where it goes. A warm brown all over and a warm brown only on the strands of a balayage are two different results.

So now there is a simple switch, "The colour goes on", with two options: all over or strands only. When the stylist picks a technique that works on strands, the tablet switches to "strands only" by itself, because that is almost always what is needed. But if the stylist changes it by hand, the tablet respects that choice and does not quietly undo it. A small label on screen always shows what is being tried: "Base" or "Strands", with the colour name.

A history of previews, like at the chair

Each preview takes about thirty seconds, and the tablet says so clearly while it works. The result is shown full screen; holding a finger down brings back the original, and letting go shows the preview again. It is the most natural way to compare.

Previews line up in a history that always starts with "Her now": the starting photo. From there you can move on in two ways:

  • start over, applying the whole recipe again to the original photo (useful when several things change at once);
  • adjust this photo, starting from the latest preview and changing a single detail, for example "a bit cooler".

If the client says "the one before was better", you tap the one before and continue from there: the history opens a new branch without losing the other previews. That is how people actually reason at the chair, trying and stepping back.

For undecided clients there is the warm and cool comparison: both versions start together and arrive side by side, again in about thirty seconds. The choice is often made right there, in a few moments, looking at the two images next to each other. The Miraviso site has a practical guide on exactly this situation, in Italian: the client who can't decide on a colour.

At the end, the before and after can be replayed with a wipe animation, built directly on the tablet.

The part where I made no compromises

This is a person's face, and it has to be treated accordingly. To generate the preview the photo goes through a Google model (Gemini) running on servers in Europe, not on the generic worldwide ones. I say it openly because it is different from the live try-on, which never leaves the device.

The rules are these:

  • without the client's consent the consultation does not start: the server refuses the request, it is not just a notice on screen;
  • on the server the photo stays only in memory while the preview is generated, it is not written to disk;
  • the preview history lives on the tablet, not on the server; the look is saved to the client record only if the client has also agreed to photos being kept;
  • every image carries the label "AI-generated preview", as required by the EU rules on artificial intelligence: the client must know it is a simulation, not a promise.

That last point matters for the salon too. A preview helps people understand each other, it does not guarantee the result: the starting base, the condition of the hair and the stylist's hand still decide, and the label says so without having to explain it every time.

What changes for the salon

The value is not in the technology, it is in the conversation. A consultation where the client sees three or four variations and picks the one she likes is one where you understand each other earlier, and where suggesting an extra service gets easier, because she sees it on herself instead of imagining it.

If you work in a salon and want to handle this moment better, even without a tablet, the Miraviso site has practical guides (in Italian) written for the chair, starting with the questions to ask in a colour consultation.

If your app or business software handles client photos or personal data and you want to check where that data goes and which consents you need, we can look at it together on a free 30-minute call.

Originally published at gabrielepieretti.dev. I write about software for small businesses, Laravel, FastAPI and privacy-by-design. More here.