Ahrefs vs Apple Notes vs Obsidian vs Spacer
| Attribute | ||||
|---|---|---|---|---|
| Category | SEO & Search Marketing | Note-taking & Knowledge | Note-taking & Knowledge | Document Management |
| Pricing | Freemium | Free tier | Free tier | Free tier |
| Starting price | $129 | $0.99/month | $4/seat/month | $15/month |
| Free tier | No | Yes | Yes | Yes |
| Free trial | Yes | No | No | No |
| Deployment | Cloud | — | Cloud | — |
| API available | Yes | Unknown | Unknown | Unknown |
| Platforms | — | — | ios, android, windows, macos, linux | — |
| Certifications | — | — | — | — |
| Integrations | — | — | 2 | — |
| Company | Founded 2010 | — | Founded 2020 | — |
| Feature attributes | ||||
| Sso Saml | ✓ Yes | — Unknown | — Unknown | — Unknown |
| Rbac | ✓ Yes | — Unknown | — Unknown | — Unknown |
| Mobile App | — Unknown | — Unknown | — Unknown | — Unknown |
| Webhooks | — Unknown | — Unknown | — Unknown | — Unknown |
| Data Export | ✓ Yes | — Unknown | — Unknown | — Unknown |
| Keyword Research | ✓ Yes | — Unknown | — Unknown | — Unknown |
| Backlink Analysis | ✓ Yes | — Unknown | — Unknown | — Unknown |
| Rank Tracking | ✓ Yes | — Unknown | — Unknown | — Unknown |
| Site Audit | ✓ Yes | — Unknown | — Unknown | — Unknown |
| Index Size | — Unknown | — Unknown | — Unknown | — Unknown |
Also consider
Unknown values show as “Unknown”/“—”. Nothing is inferred — see each tool page for sources.