How it works
Corneo reads the shelf you already own, fills only the gaps from a curated catalog, and paces your actives so your barrier keeps up.
Audit your shelf.
Tell Corneo what you own. It checks each product against a short set of rules and tells you what belongs in your routine tonight, what clashes, and what to set aside for now.
Your routine, 1 change
4 products read. All 4 are in the plan.
- Hydrating cleanser
- Daily moisturiser
- Mineral SPF 50catalog pick
- Hydrating cleanser
- Heartleaf toner
- Retinal 0.05%Mon, Thu
- Daily moisturiser
Why it parks things
The rules are the ones a careful dermatologist applies before anything else. Sunscreen every morning if you use a retinoid or an exfoliating acid. Retinoids and acids on different nights. Benzoyl peroxide never in the same session as a retinoid or vitamin C. One retinoid product at most, and only in the evening.
If your skin is reactive right now, treatment actives pause for a week or two and the routine becomes a repair one: gentle cleanser, ceramide moisturiser, mineral sunscreen. Nothing is thrown away. A parked product shows why it is parked and when it comes back.
Fill the gaps, not the cart.
If your shelf already covers a step, Corneo uses what you have. Only the steps you are missing get a suggestion, from a small catalog chosen by hand.
Thursday AM
3 steps, about 3 minutes
Next change: Retinal 0.05% steps up to 3 nights around week 5.
How products are chosen
A routine has four slots: cleanse, treat, moisturise, protect. Each empty slot is filled by a fixed lookup against the catalog for that slot, your constraints and your budget, in a set order. Two people with the same shelf and the same answers get the same result. No model picks a product, and nothing is ranked by commission.
The catalog is short on purpose. Each entry carries the reason it was chosen and how strong the evidence behind it is, and you can read both before you buy anything.
Step up only when your skin says so.
A new active starts at two nights a week. Corneo moves you up only after you have actually done those nights, and holds or restarts if you have not.
How the pace is set
A retinoid schedule runs about twelve weeks: two nights a week, then three, then four or more by tolerance. Each step up is gated on the nights you actually logged, and the numbers are under "Why it waits" below.
Irritation logged within three days of a step up offers a step back down. Barrier SOS pauses the clock without losing what you built.
What Corneo checks
Eight hard rules, applied to every routine before you see it. Each one blocks; none of them is a suggestion. They are the same for everyone, and they are written down.
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H1Sunscreen every morning if your routine has a retinoid, adapalene, an exfoliating acid or benzoyl peroxide. -
H2A retinoid and an exfoliating acid never go in the same session on the same day. -
H3Benzoyl peroxide and a retinoid never go in the same session. Adapalene is the one exception, because it is stable with it. -
H4Benzoyl peroxide and vitamin C (L-ascorbic acid) never go in the same session. -
H5Retinoids go on in the evening only. -
H6One retinoid product in the routine, at most. -
H7On a pregnancy-safe routine, no retinoids and no high-dose salicylic acid. Azelaic acid takes the slot. -
H8If your barrier is compromised, every treatment active is paused and the routine becomes a repair one: gentle cleanser, ceramide moisturiser, mineral sunscreen.
The six soft rules
These warn and allow. You see the note, and the step stays in.
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S1Vitamin C and niacinamide in the same session. A largely outdated concern, so it is a note, not a block. -
S2Copper peptides with vitamin C or an exfoliating acid in the same session. -
S3More than two exfoliation sessions a week on sensitive skin. -
S4A beginner retinoid scheduled more than two nights a week. This is what the pacing schedule below enforces. -
S5More than seven steps in one session. -
S6If you tan rather than burn, exfoliants are capped: no scrubs, no glycolic above 10 percent, mandelic or lactic preferred.
Why it waits
A new active steps up on what you did, not on the calendar. When a stage ends, Corneo counts the nights you logged the product against the nights it was scheduled. At 70 percent or more, you step up. Between 30 and 70 percent, the stage holds for another two weeks.
| Stage | Mon | Tue | Wed | Thu | Fri | Sat | Sun | Nights a week |
|---|---|---|---|---|---|---|---|---|
| Weeks 1 to 4 | Mon, yes | Tue, no | Wed, no | Thu, yes | Fri, no | Sat, no | Sun, no | 2 nights |
| Weeks 5 to 8 | Mon, yes | Tue, no | Wed, yes | Thu, no | Fri, yes | Sat, no | Sun, no | 3 nights |
| Weeks 9 to 12 | Mon, yes | Tue, no | Wed, yes | Thu, no | Fri, yes | Sat, no | Sun, yes | 4 nights |
Below 30 percent the stage starts over. Skin that was not exposed built no tolerance, and a lapsed user is never stepped up into a dose they have no tolerance for. None of this is phrased as a failure; it is the app doing its job. Stepping up anyway is yours to choose, and it is logged.
What Corneo will never do
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Scan your face. No face or skin photo is ever an input to your routine. The only photo Corneo reads is your shelf, to read labels.
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Prescribe a wholesale routine. Corneo manages what you own and fills the gaps. It does not replace your shelf with its own.
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Count streaks. No streaks, no adherence score, no guilt. Corneo records what happened and never claims a product caused a change in your skin.
Questions
Does it scan my face?
No, and it never will. The only photo Corneo reads is your shelf, to read the labels. A photo of your face or skin is never an input to your routine.
What happens to my photos?
A photo you take to read labels is sent to the Anthropic API for that reading and is not stored. A photo you add to a product on your Shelf, or to your timeline to compare against later, is stored in a private folder that belongs to your account, is never analysed, and is removed when you delete your account.
Is it medical advice?
No. Corneo checks a routine against the rules above and paces actives. It does not diagnose, treat, or claim that a product changed your skin. Anything that stings, spreads or does not settle is a question for a clinician, not an app.
Which products does it recommend?
Only ones from a short catalog chosen by hand, and only to fill a step your shelf does not cover. If you already own something for a step, that is what goes in. For most people who arrive with a routine, the gap is sunscreen or nothing. Nothing is ranked by commission, and each entry shows why it was chosen.
Does it work if I already have a routine?
Yes. That is Audit mode: with three or more products on your shelf, Corneo leads with what it found about what you own instead of a prescription. What checks out stays, and what clashes is parked with the reason and the condition that brings it back.
When can I get it?
Corneo is in a small private test on iPhone through TestFlight. Leave your email below and the next invite goes to you. The App Store comes after the test.