Undertint

Undertint helps watercolour painters answer one question: how do I mix that colour, with the paints I already have?

Point Undertint at a photo. The app simplifies the image into the colours you would actually need to paint, then gives you a mixing recipe for each one, drawn from your own palette. Recipes use Kubelka-Munk pigment mixing, the same maths colour scientists use to model how watercolour pigments combine on paper. The output is a recipe you can mix at the page, not a colour you can only see on a screen.

Everything happens on your device. Photos never leave your phone. There are no accounts, no sign-up, no subscriptions, and no internet connection required.

Features
• Photo simplification with adjustable detail. Pull the slider down for big colour shapes, up for finer control.
• Tap any region to see the colour identified in painterly terms and a Munsell reading.
• Mixing recipes from your own paints. The first release covers Winsor & Newton Professional Watercolour, Holbein Artists' Water Color, and Daniel Smith Extra Fine Watercolors.
• Dilution gradients show how a colour shifts as you add water, so you can match the value as well as the hue.
• Save value studies to your photo library to use as on-easel references.
• Full iPad support including landscape and Apple Pencil.

Who it's for
Watercolourists who want to spend less time second-guessing colour mixes and more time painting.
Beginners learning what their paints can do, and experienced painters who want a quick second opinion when matching a tricky reference colour.

What Undertint isn't
Undertint isn't a digital painting app. It doesn't replace mixing on your palette. It helps you decide and learn how to mix.

About brand names
Brand and product names referenced in the catalogue are trademarks of their respective owners. Undertint is independent of, and not affiliated with, Winsor & Newton, Holbein, or Daniel Smith.

Privacy
Undertint does not collect, transmit, or sell your data. No analytics, no advertising, no third-party SDKs, no network requests. Photos you import are processed on-device and never leave your phone.