Delta Chat vs otr.to
Delta Chat
delta.chatotr.to
otr.toSide by side
| Figure | Delta Chat | otr.to |
|---|---|---|
| Price from | Free | — |
| Free plan | Yes | — |
| Free trial | — | — |
| Open source | — | — |
| Web | — | Yes |
| Windows | Yes | — |
| macOS | Yes | — |
| Linux | Yes | — |
| iOS | Yes | — |
| Android | Yes | — |
| Self-hosted | Yes | — |
| Plans published | 1 | 0 |
| Spec score · Encrypted Messaging Apps | 8.3 (#4) | 5.9 (#43) |
| Product | Delta Chat is a reliable, decentralized and secure instant messaging app for mobile and desktop. | otr.to is a browser based tool for peer to peer chat. |
Plans
In their own words
Delta Chat
Delta Chat is a free, open-source instant messaging app for mobile and desktop, with support for self-hosting. It runs on Android, iOS, Linux, macOS and Windows, and supports multiple profiles and devices. Messages travel through secure, interoperable chatmail relays and are end-to-end encrypted by default, including attachments and their metadata. Delta Chat uses a subset of OpenPGP with Secure-Join and Autocrypt. Servers can still see sender and receiver addresses and message size; other message, contact and group metadata is encrypted. Chats can include interactive web apps for gaming and collaboration. Android and iOS audio and video calls use peer-to-peer WebRTC, but a March 2026 post said the feature was still behind a debug setting. A classic email address can act as a relay only if used exclusively by chatmail clients, and classic email providers generally do not support push notifications. The FAQ says there are no immediate plans for a web client. The project links to a forum for support and feedback.