Canva
canva.com — free, best for slides, PPT decks, and general design work (thumbnails, social graphics, presentations). Not a diagramming tool per se — use it for the presentation layer around diagrams produced in Eraser or Figma, not for the architecture diagrams themselves.
UI mockup → dev hand-off: Canva can also serve as a fast wireframe/mockup tool (layout, palette, typography, visual assets) that gets handed to developers via:
- Asset export — SVG/high-res PNG for icons and illustrations, embedded straight into frontend code.
- PDF/image wireframes — full-page mockups as visual blueprints for spacing, alignment, and layout intent.
- Shareable view links — devs inspect layout/proportions and pull copy directly.
It's a lightweight option, not a substitute for a real UI/UX design tool when the project needs precise dev hand-off (auto-generated CSS, exact padding/margins, design tokens, interactive prototyping) — for that, use Figma (industry standard, click-to-inspect CSS/HEX/flex properties), Penpot (open-source, native SVG/CSS web tool), or Adobe_XD (interactive wireframing/prototyping with spec sharing).
Hand-off hygiene regardless of tool: export vector assets as SVG (crisp at any resolution, small file size); hand over a defined color palette (HEX) and type scale so devs can set CSS variables/theme tokens; design both desktop and mobile viewports so devs know how layout should reflow.