InInbox vs Substack
| InInbox | Substack | |
|---|---|---|
| Free plan | No | No |
| Free trial | No | No |
| Paid from | — | — |
| Open source | No | No |
| Platforms | Web | Web, iOS, Android |
| Free plan | No | Yes |
| Monthly send limit | 1,000,000 emails/mo | — |
| Email automation | — | Yes |
| Audience segmentation | — | Yes |
Both are listed in Best Email Marketing Software. On Samsung Mobile US Press, Substack scores higher on our published basis.