Caddis: DWG & CAD Viewer

Open DWG, DXF, STL, STEP, IFC and SolidWorks files on iPhone & iPad. Measure, mark up, and share reviews — fast, offline, and private, with no account or cloud upload.

Caddis is the fast, private way to open and review CAD drawings and 3D models on iPhone and iPad — no account, no sign-up, no cloud upload. Open a DWG, DXF, STL, STEP, OBJ, PLY, IFC, or SolidWorks file straight from Files, then measure it, mark it up, and share your review in seconds.

WHY CADDIS

• Fast — files are parsed and rendered right on your device • Private — no ads, no analytics, no tracking, no account. A file leaves the app only when you tap Share. • Offline — review drawings on-site, in the field, or on a plane with no connection

REVIEW TOOLS

• Pan, zoom, fit, rotate, and orbit 2D drawings and 3D models • Measure distance, angle, area, and perimeter • Display in feet, feet and inches, inches, US survey feet, meters, or millimeters • Mark up with notes, arrows, rectangles, and revision clouds • Snap annotations to supported drawing geometry or mesh vertices • Toggle and isolate layers where source layers exist • Save named locations and keep your review state on-device • Share the current view as a PNG, the original file, or portable annotation JSON

SUPPORTED FORMATS

• DWG and DXF 2D drawings • STL, OBJ, and PLY 3D meshes • STEP / STP tessellated models • IFC building geometry • SolidWorks SLDPRT and SLDASM (saved display tessellation)

Caddis renders real, source-derived geometry — never a generated stand-in — and clearly reports anything it cannot open instead of faking a preview. Coverage varies by file version, exporter, and device.

FORMAT NOTES

DWG is limited to R2004 and R2010–R2018 model-space geometry (R2007 and pre-R2004 files are not supported). DXF must be ASCII. STEP/STP, IFC, and SolidWorks coverage is limited to tessellated or faceted geometry, not full parametric or BIM semantics. Some layouts, xrefs, hatches, dimensions, fonts, materials, and textures are not yet covered.

IMPORTANT

Caddis is a viewing, measuring, and markup tool — not a CAD editor or a source of engineering certification. Always confirm critical dimensions, scale, and geometry against the authoritative source before construction, fabrication, or safety decisions. Snapping targets supported geometry; the visible grid is a navigation aid.