Mounting Plate
40 × 24 × 10.5 mmA small bracket with two through-holes, a raised boss and rounded edges. The classic first part — and a quick, clean print.
- Extrude
- Fillet
- Fillet
- Extrude + union
Free & open source · iPad, iPhone & Mac Real CAD.
Real CAD.
In your hands.
OpenShape3D is a direct-modeling CAD app for iPad, iPhone and Mac. Sketch on any face, push and pull faces into exact solids, fillet edges with a fingertip — powered by the OpenCASCADE geometry kernel and a custom Metal renderer.
Free on the App Store · No account · Source on GitHub
No iPad or Mac handy? Try it in your browser
OpenCASCADE kernel
Exact B-rep solids, not just meshes
Custom Metal renderer
Crisp edges at 120 Hz
Apple Pencil
Sketch like it's paper
100% open source
Every line on GitHub
Desktop-class modeling, touch-first
The sketch–extrude–modify workflow you know from desktop CAD, rebuilt from scratch for touch.
Sketch
Sketch with exact dimensions
Pick a world plane, tap any flat face, or pull an offset plane off the model. Lines, arcs, splines, polygons and text, with snapping and Apple Pencil — then type a dimension (inline math works: 25.4/2) and a real constraint solver holds it.
Model
Push, pull and extrude
Tap a face and drag. Pull away to add material, push in to cut — the booleans happen for you. Type an exact distance any time, extrude symmetrically, and watch the preview follow your finger.
Parametric
Every step stays editable
Each extrude, fillet and pattern is recorded in the history. Change a radius from 4 mm to 2 mm and everything after it rebuilds — no starting over when the design changes.
Shape
Revolve, shell, fillet and more
Revolve a half-profile into a bottle, shell it hollow, round the lip. Sweep, loft, helix, chamfer, split and linear or circular patterns — the tools you expect from desktop CAD, on exact B-rep geometry.
Open
Free, and your files stay yours
Export STL, OBJ, 3MF, GLB, USDZ and sketch DXF, preview in AR, or save a project archive anyone can open. No account, no subscription, no cloud lock-in.
Mac
At your desk, too
The same app runs on Apple silicon Macs, with mouse, trackpad and keyboard shortcuts — and the same project files, so a part started on iPad finishes at your desk.
Video tutorials
Watch it built, tap by tap
38 free tutorials on YouTube — from your first part to threaded bolts, gears and print-in-place hinges.
How do you model this? — under a minute each
All Shorts →Sample files
Open a real design
Download a project with its full feature history and change any of it, or grab the STL and print it. Tap a model to spin it in 3D.
Plate Cam
50 × 55.7 × 8 mmA cam plate with a bore, from one sketch and one extrude — the shortest history of the four, and the easiest to start editing.
- Extrude
Glass Bottle
Ø 65 × 230 mmOne half-profile revolved into a bottle, shelled hollow through the neck, with filleted lip and base.
- Revolve
- Shell
- Fillet
- Fillet
Motorcycle Wheel
Ø 957 × 333 mmA two-body assembly — tire and rim — built from revolves, tapered extrudes, circular patterns, a mirror and booleans.
- Revolve
- Draft extrude
- Circular pattern
- Mirror
- Subtract
- +7 more
Everything in the box
Constraints & dimensions
A real 2D variational solver — coincident, tangent, symmetric, driving dimensions with inline math, live DOF feedback.
Exact B-rep solids
Powered by the OpenCASCADE geometry kernel — the same class of engine behind desktop CAD.
Import & export
Bring in STL and DXF. Send out STL, OBJ, 3MF, GLB, USDZ and DXF — or open your model in AR Quick Look.
Booleans
Union, subtract and intersect between bodies — plus automatic booleans on every push/pull.
Revolve, sweep, loft & helix
Take any sketch profile along an axis, a spine, ordered sections, or a helical path.
Transform gizmos
Move, rotate, scale, mirror, translate and align with snapping — or type exact values.
Section & isolate
Clip the model live against any plane with a draggable cut, or isolate just the selection.
Materials
Steel, aluminum, brass, plastics, rubber, wood — or custom color with metallic and roughness sliders.
Measure
Face area, body volume, bounding box and point-to-point distance, straight from the model.
The whole workshop, in your pocket
The full toolset runs on iPhone too — same kernel, same renderer, same models.
Open source, all the way down
OpenShape3D is built in the open — SwiftUI, a custom Metal renderer, a pure-Swift constraint solver, and the OpenCASCADE B-rep kernel with the Euclid mesh library alongside it. Read the code, file issues, or contribute a feature.