How to paint a 3D model on your phone

Before you start: the two gestures

The entire control scheme of a 3D painter on a phone is this:

• One finger paints.
• Two fingers orbit and pinch-zoom.

In Spin & Paint there are two more worth learning on day one, both borrowed from desktop art software: two-finger tap undoes and three fingers redo, up to 50 steps. They are much faster than reaching for a button mid-stroke, and knowing undo is one tap away is what makes people brave enough to try things.

Step by step

1. Pick a model with clear separate parts. For a first attempt, a character with distinct clothing, skin and hair is far easier than an intricately patterned one. You want obvious regions.
2. Block in the big areas first. Large brush, low detail, get every part of the model roughly the right color before you refine anything. Working large-to-small is the single habit that most improves a first result, and the one beginners most often skip.
3. Turn it as you go. Rotate every minute or so. The classic beginner outcome is a beautifully finished front and a completely blank back, discovered forty minutes in.
4. Then refine, region by region. Now zoom in and do the face, the hands, the details. Because the base is already down, mistakes here are small and local.
5. Add depth last. A slightly darker tone in the creases and a lighter one on raised edges is what makes a 3D paint job read as sculpted rather than filled in. The airbrush at low opacity is the tool for this.

The tool that changes everything: zone selection

The zone selector lets you select a region of the model and then paint freely inside it — nothing spills over the edge. It is the closest thing to a line to stay inside, available on demand.

Use it whenever two areas meet and you want a clean boundary: a sleeve against a hand, hair against a forehead, a boot against a leg. Select the region, then paint as carelessly as you like. This one tool is the difference between a result that looks deliberate and one that looks smudged.

Four mistakes worth skipping

1. Starting with detail. Painting a beautiful eye onto an otherwise blank model almost always ends in repainting the eye, because the colors around it change everything about it.
2. Using pure black for shadows. A darker version of the base color reads as shadow; black reads as a hole. Same for pure white as highlight.
3. Too many colors. Three or four with a couple of tints beats twelve. The models in the museum are small objects, and small objects get noisy fast.
4. Not zooming out. Pinch out every few minutes and look at the whole thing. Problems that are invisible at 200% are obvious at 100%.

Changing how it looks without repainting

There are six view modes, and switching between them costs nothing: shaded 3D, glossy, flat albedo, comic cel-shading, wireframe, and a rainbow normals view. Flat albedo is genuinely useful while working — it strips the lighting so you can see your actual colors rather than what the light is doing to them. Glossy and cel-shading are worth trying on a finished piece; the same paint job can look like two different objects.

On a phone versus an iPad

Everything above works on both. On iPad you additionally get Apple Pencil pressure and tilt, palm rejection so you can rest your hand, and a hover cursor that shows the brush footprint before you touch down — which changes how the detail pass in step 4 feels quite a lot. More on Apple Pencil support.

Both have left- and right-handed layouts, and four quality tiers so older devices stay smooth.

When you are done

It saves itself as you work, so there is no moment where you have to commit. When you want to keep it, save the piece to Photos or share a spinning video that shows every side — how to do that.

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