Kastle alternatives
TL;DR: 12 companies doing similar work to Kastle in B2B, ranked by how closely they match what Kastle actually does — not just by category.
How this list was built: every company here is Y Combinator-backed and shares at least one category with Kastle. They are scored on how closely their own description overlaps with Kastle's, and all facts shown come from the YC company records — nothing is estimated.
What are the best alternatives to Kastle?
| Alternative | What it does | Batch | Team | Status |
|---|---|---|---|---|
| Fithub | — | Winter 2010 | — | Inactive |
| Insoshi | — | Winter 2008 | — | Inactive |
| Brushes | iPad drawing software. | Summer 2010 | — | Inactive |
| BookSolid | BookSolid is the opentable for tour operators. | Winter 2012 | — | Inactive |
| SolidStage | Sysadmin as a service. We make deploying, configuring, monitoring,… | Winter 2012 | — | Inactive |
| Optilly/Installmonetizer | Fb ad optimization platform | Winter 2012 | 11 | Inactive |
| LaunchHear | LaunchHear was a startup attempting to make PR scale in the same way… | Winter 2010 | 2 | Inactive |
| Button Computer | The tiny computer built for voice AI. | Winter 2026 | 1 | Active |
| Tumult | Tumult is building the next generation of apps for web design. Our… | Winter 2011 | 1 | Active |
| GiveSpark | Givespark was a celebrity charity fundraising platform | Winter 2012 | 1 | Inactive |
| Presto | Digital meets physical for big chain restaurants | Summer 2010 | 200 | Public |
| Cofia | AI automations that implement themselves | Winter 2026 | 3 | Active |
Is Kastle still active?
Kastle is still operating, so switching is a choice rather than a forced migration. Compare on fit and price rather than urgency.
How was this list put together?
Every company here is Y Combinator-backed and shares at least one category with Kastle. They are then ranked on how closely their own description overlaps with Kastle's, so the closest matches come first rather than whoever happens to share a tag.