Nostrmo is a free, open-source client for Nostr, the decentralized social network protocol, written in Dart and Flutter. It is aimed at people who want to post, follow and read across relays without depending on a single company's servers, and who want one app that runs on several operating systems. On Windows it is distributed through the Scoop package manager, which makes it a quick install for anyone comfortable with the command line.
Nostrmo is released under the GPL-3.0 license, and its latest version is 3.5.1, with the most recent code update dated May 27, 2026. The project supports a broad set of Nostr Improvement Proposals, though a few older ones are marked as deprecated, most notably NIP-04 encrypted direct messages, which the project recommends replacing with NIP-44. Read on for the features, installation steps and the safety checks worth doing before you sign in with your keys.
What Is Nostrmo and Who Is It For?
Nostrmo is a desktop and mobile client for Nostr, so it is the app you open to read and write posts, not a server you run for others. It suits three kinds of readers. The first is someone who wants to try Nostr without committing to a single platform, since the same project covers Windows, macOS, Linux, Android, iOS and web. The second is a Windows user who prefers installing software from a package manager and keeping it updated with a short command. The third is a developer or tinkerer who wants to read an open-source Flutter codebase and see how a Nostr client handles events, relays and keys.
It is less suited to someone who expects a polished, fully managed service with a support desk. Nostrmo is a community-driven open-source project, so the documentation and FAQ on GitHub are the main places to find answers. Readers who are comfortable reading release notes and checking downloads will get the most from it.
How Keys, Relays and Identity Fit Together
Nostr works differently from most social networks. Your account is a key pair: a public key that others use to find you and a private key that proves a message came from you. Nothing requires a company to approve your account, and no single server owns your profile.
Posts are sent as signed events to relays, which are servers that store and pass events along. You can publish to several relays at once, and reading from a mix of relays usually gives a fuller picture of the network. When you choose relays, you are choosing where your posts are stored and how easily others can find them.
Identity is layered on top of keys. A readable identifier such as a NIP-05 address is a convenience that points back to your public key, and it is only as trustworthy as the domain behind it. Understanding this split helps you decide what to share publicly and what to keep private.
Real-World Scenarios for a Flutter Nostr Client
A freelance writer might use Nostrmo on a Windows laptop to publish long-form notes and reply to readers, then check the same feed on a phone during a commute. Because the protocol is shared, the posts remain the same across apps, and the writer only needs to keep the account keys safe.
A community organizer could follow a list of local members and use replies and threads to coordinate events. Nostr's threading conventions, described in NIP-10, keep replies attached to the right conversation, which matters when several groups talk in the same feed.
A developer evaluating relays might open Nostrmo to compare how different relays respond, using relay information documents to check supported features. The app becomes a practical test bench as well as a reading tool, especially for people who want to understand the protocol in action rather than in theory.
Why Open Source and a Flutter Codebase Matter
Nostrmo is released under GPL-3.0, a copyleft license. In plain terms, anyone can read the source code, modify it and share changes, but derivative works must remain open under the same license. For users, this means the behavior of the app can be inspected rather than taken on trust.
The project is written in Dart and built with Flutter, Google's toolkit for building apps from one codebase. A single codebase is one reason the project can target several platforms. It also means developers who already know Dart or Flutter can contribute fixes and read the logic without learning a separate language for each system.
Open source does not guarantee that every change is safe, but it gives reviewers a way to check. Keeping an eye on the project's release history and the GitHub repository is a sensible habit for any software that touches your keys.
Key features
Core Protocol Flow (NIP-01)
Follow Lists (NIP-02)
DNS-Based Identifiers (NIP-05)
Key Derivation From a Seed Phrase (NIP-06)
Browser Signing (NIP-07)
Deletion and Threaded Replies (NIP-09 and NIP-10)
Relay Information and Proof of Work (NIP-11 and NIP-13)
Timestamped Events (NIP-03)
Supported coins
The project documentation mentions the Lightning Network and Nostr itself as the networks and protocols the app relates to. Lightning is a second-layer payment network built on Bitcoin, while Nostr is the social protocol that Nostrmo is built around. The documentation does not turn this into a list of supported coins, so readers should treat the Lightning reference as context for the ecosystem rather than a promise of specific payment features.
How to install Nostrmo on Windows
PS> scoop install nostrmo- 1
Check That Scoop Is Installed
Scoop is a command-line package manager for Windows. If you do not have it yet, install it first using the instructions on its official website, then open PowerShell. Scoop takes care of downloads and folders, so you do not need to search for installers by hand.
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Install Nostrmo With One Command
In PowerShell, run scoop install nostrmo. Scoop downloads the package and places it in its apps folder, then creates a shortcut. Wait for the command to finish and check the output for any errors before opening the app.
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Launch and Keep It Updated
Open Nostrmo from the Start menu or run it from the Scoop apps folder. To pick up later releases, run scoop update nostrmo periodically. Each update is a new version of the same app, so your data and keys remain under your control.
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Download Directly if You Prefer
If you do not want to use Scoop, download the Windows build only from the official website or the project's GitHub Releases page. Before running the file, verify its SHA-256 checksum or signature, as described in the safety section below. Then run the installer and follow the on-screen prompts.
How to use Nostrmo
Nostrmo works best once you understand that Nostr has no central account. Your identity is a key pair, and relays store and pass along your signed events. Plan how you will back up your keys before you post anything.
- Open Nostrmo and create an account or import an existing Nostr key. If you are new, generate a key and write down any backup phrase on paper, kept offline.
- Add the relays you want to use. Choose relays you trust, and check their relay information where the client makes it available.
- Fill in your profile. If you have a domain or a trusted identifier provider, add a NIP-05 identifier so others can recognize your name.
- Follow a few accounts, then let your feed fill in. Starting small makes it easier to see how threads, replies and profiles display.
- Publish a note, reply to an existing one, or delete one of your own posts. Deletion uses the NIP-09 request, which asks relays to remove the event but cannot force every copy to disappear.
- Review your direct message setup. Prefer NIP-44 encryption over NIP-04 where your contacts support it, since NIP-04 is marked as deprecated.
Take these steps slowly, test with a small account if you can, and keep your key backup somewhere offline.
Pros & cons
- Free and open source under GPL-3.0, so the code can be inspected
- Covers Windows, macOS, Linux, Android, iOS and web from one Flutter codebase
- Installs on Windows with a single Scoop command
- Supports a wide range of NIPs, including follow lists, relay information and threading
- Recent code update on May 27, 2026, with version 3.5.1 as the latest release
- Public FAQ on GitHub for common questions
- Windows installation depends on Scoop, so people without it need an extra setup step
- NIP-04 encrypted direct messages are marked as deprecated in favor of NIP-44
- NIP-08 is also marked as deprecated in favor of NIP-27
- NIP-89 (Recommended Application Handlers) is still unchecked in the project's support list
- Newcomers to Nostr may need time to understand keys, relays and identifiers
Is Nostrmo safe?
Nostrmo is open source under GPL-3.0, which means its code can be reviewed. Download only from the official website, the project's GitHub repository or its Releases page, or install through Scoop with scoop install nostrmo. Before running any downloaded file, compare its SHA-256 checksum with the value published on the release page, or check the signature if one is provided. Nostrmo handles Nostr keys, and NIP-06 links keys to a seed phrase, so never type your seed phrase or private key into third-party websites, chat apps or support forms. Be cautious of fake clones and sponsored search results. Check the latest version on the official website before updating; the most recent code update was dated May 27, 2026.
- Official source only. Download from github.com/haorendashu/nostrmo. Ignore ads and lookalike domains.
- Check the SHA-256. Compare the installer hash with the value the developer publishes before running it.
- Never share your seed phrase. No developer, support agent or website — including CryptApps — will ever ask for it.
Alternatives
Among the clients in this catalog, Nostrmo stands out for covering the most platforms from a single codebase, including Windows, macOS, Linux, Android, iOS and web. Vega is also a cross-platform desktop client, so it competes most directly on the desktop. Nostrid offers binaries for Android, Windows, macOS and Linux, a similar range that leans toward native downloads. Notedeck takes a different approach as a Rust-based desktop browser from Damus, while Blockcore Notes is a Progressive Web App that you install from the browser on mobile or desktop. Amethyst is another Nostr client worth comparing. Choose by the platforms you use first, then by the NIPs and interface style that fit your habits.
Specifications
- Price
- Free
- Type
- Open source
- License
- GPL-3.0
- Latest version
- 3.5.1
- Last update
- 27 May 2026
- Windows support
- Yes (available via Scoop)
- Source code
- github.com/haorendashu/nostrmo
- Install command
- scoop install nostrmo
Frequently asked questions
Yes. Nostrmo is free and open source under the GPL-3.0 license, so you can use it, study its code and share modified versions under the terms of that license. Installing it on Windows through Scoop involves no purchase, and the project does not require a paid plan to read or post.
Install Scoop first, then open PowerShell and run scoop install nostrmo. Scoop downloads the package and sets up the app for you. Later, scoop update nostrmo brings in newer releases, which keeps the installation current without repeating manual downloads.
The code is open source, so it can be reviewed, but safety also depends on how you install it and how you handle your keys. Verify downloads with a checksum or signature, avoid unofficial copies, and never enter your seed phrase on a website you do not fully trust. Those habits matter more than the app itself.
Nostr is a decentralized protocol for social apps. Users are identified by public keys, and they send signed events through relays that store and pass them along. No single company controls accounts, so you can move between clients while keeping the same identity and follow list.
The project documentation mentions the Lightning Network, which shows the app relates to that ecosystem. For details about specific payment features, check the project's FAQ on GitHub or its documentation, since the exact behavior is what matters before you rely on it.
NIP-04 is an older standard for encrypted direct messages, and the project marks it as unrecommended in favor of NIP-44. You can still see the feature in the app, but NIP-44 is the better choice when your contacts support it. Ask your contacts which encryption they use before sending sensitive messages.
Yes, the project lists Android and iOS among its supported platforms, so the same app family covers phones as well as Windows. Installation on those devices follows each platform's own methods, so check the official project information for the correct package for your device.
Verdict
Nostrmo suits Windows users who want a free, open-source Nostr client that also runs on macOS, Linux, phones and the web. It fits people who are comfortable installing through Scoop or verifying a download by hand, and developers who want to study a Flutter-based protocol client. If you rely on encrypted direct messages, prefer NIP-44 and test with a small account first. Keep your seed phrase offline, and check the latest version on the official website before updating.