Strengths
- The widest format list here: Altium (SchDoc, PcbDoc), EAGLE (SCH, BRD), Gerber RS-274X and X2, ODB++, KiCad in beta, and ZIP, 7z or RAR packages.
- Gerber Compare shows two Gerber sets against each other before you send one to the fab.
- 2D PCB measurements between two points.
- By default the design is removed when you close the browser tab.
What it can't do
- KiCad support is labelled beta.
- Files are uploaded to Altium; uploading means agreeing to its privacy policy and terms of use.
- Shared links last only for a limited period, and keeping a design needs an Altium 365 personal space.
- A viewer, not a place to keep or continue a KiCad project.
VerdictThe most versatile multi-format viewer: pick it when files arrive from many CAD tools, less so for KiCad-first work.