Calculate the correct drill bit size for your tapping operations. Supports various thread types and inch/metric measurements. Provides precise calculations for depth of thread and clearance.






241+ iOS apps & games curated and reviewed
The best tap drill apps and games on iPhone average 4.1★ across 241+ titles — we've ranked them by what real users actually keep on their phones. Updated October 2026.
| # | App | Price | Rating | Ads | In-App Purchases | Updated | |
|---|---|---|---|---|---|---|---|
| 1 | Free | — | No | No | May 2026 | ||
| 2 | Free | — | No | Yes | Oct 2026 | ||
| 3 | $1.99 | 4.3★ (30) | No | No | Oct 2026 | ||
| 4 | $0.99 | — | No | No | Oct 2026 | ||
| 5 | Free | — | No | Yes | Oct 2026 | ||
| 6 | Free | — | — | No | Oct 2026 | ||
| 7 | $1.99 | 1.0★ (1) | No | Yes | Nov 2026 | ||
| 8 | Free | 4.4★ (148) | Yes | Yes | Oct 2026 |
















Calculate the correct drill bit size for your tapping operations. Supports various thread types and inch/metric measurements. Provides precise calculations for depth of thread and clearance.