drop

Cited · Honest · Yours

Your routine might already be done.

The skincare app that cites its sources, tells you when your routine is complete, and helps you simplify — instead of selling you more products.

example what a routine read comes back with
Solid routine

This routine looks solid.

The basics are covered and the products work together. No changes recommended.

WorksParabens (a common preservative)The cancer scare rested on weak, overstated evidence, and decades of data show a good safety record.Sasseville 2015 · Dermatitis · expert consensus

Every answer names its study and links it. Nothing is recommended to you, and nothing is for sale on this page.

223cited claims234published sources643ingredient pages
Try it without the app

The app launches on iOS and Android in October 2026. Rate your own routine below — cited, no sign-in, no account.

What the three words mean
Cited.
Every evidence flag links to a published source, tiered so you can weigh it.
Honest.
When your routine is complete, we say so.
Yours.
Private by default. No ads. No data sales.
The app knows what’s already on your shelf

Both tools above work without an account, and both answer one question at a time. Once Drop knows your shelf, the question becomes “does this fit my routine?” instead of “do these five things get along?”

example what a product check comes back with

Does this fit the routine you already have?

Considering: a benzoyl peroxide wash

DailyCompatible · notes
WeekendCompatible
CautionRetinol + benzoyl peroxide — benzoyl peroxide degrades tretinoin in light, and retinol likely shares that pathway, though direct data is thin. Use them at different times of day, or alternate nights.Martin 1998 · British Journal of Dermatology · mechanistic ↗

How it fits: adds a step — nothing on that shelf does the same job. The fix here is timing, not another purchase.

It does the swap math. When something you are considering does a job a product you own already does, Drop names that product and says what swapping would cost you: the same number of steps, not one more.

It tells you when the evidence moves. Roughly quarterly, we re-read the sources behind our flags. If one of them changes for something you own, the app says so — and that is the only reason Drop will ever notify you about a product you already have.

Why Drop is built this way

I asked a skincare app how I’d know when I had enough. It answered with four more products. There was no version of that business that could answer differently. So I read what the dermatology research actually says: usually less is enough — a cleanser, a moisturizer, sunscreen, and one or two things you picked for a reason. Drop will tell you when you’re already there, even though we earn on the links.

Drop is free, and nothing on this page is for sale. We earn a commission only if you buy something through a link — after the app has told you whether you need anything at all.

How Drop earns →
Every ingredient we flag has a page