4SecureMail vs Shutbox
| 4SecureMail | Shutbox | |
|---|---|---|
| Free plan | No | No |
| Free trial | Yes | No |
| Paid from | $5/mo | — |
| Open source | No | No |
| Platforms | Android, iOS, Linux, macOS, Web, Windows | Web |
| Free plan | No | Yes |
| Paid from | 8.24 /mo | 1.99 /mo |
| Encryption scope | transport_only | — |
| Custom domains | Yes | Yes |
| Mailbox storage | 0.5 GB | — |
| Email aliases | 3 aliases | — |
| IMAP support | Yes | — |
| Private calendar | No | — |
Both are listed in Best Private Email Services. On Samsung Mobile US Press, 4SecureMail scores higher on our published basis.