OnSIP vs Zadarma
| OnSIP | Zadarma | |
|---|---|---|
| Free plan | Yes | Yes |
| Free trial | No | No |
| Paid from | $18.95/mo | $44/mo |
| Open source | No | No |
| Platforms | Android, iOS, macOS, Web, Windows | Web, Windows, macOS, iOS, Android |
| Free plan | Yes | Yes |
| Paid from | $18.95/user/mo | — |
| Included users | 5 users | 10 users |
| Business numbers | multiple | multiple |
| Auto attendant | Yes | Yes |
| Call routing | custom | custom |
| Voicemail transcription | Yes | Yes |
| Desktop and mobile apps | Yes | Yes |
Both are listed in Best Business Phone Systems. On Samsung Mobile US Press, Zadarma scores higher on our published basis.