Mattermost Mobile Guide: Setup, Troubleshooting

The Mattermost mobile app lets you access your self-hosted Mattermost server from iOS or Android. Download it from the App Store or Google Play, connect to your custom server URL, and you can message your team from anywhere. This guide walks you through setup, common login problems, and push notification options for self-hosted deployments.

Download and Install the Mattermost Mobile App

Find the official Mattermost mobile app on the Apple App Store (search "Mattermost") or Google Play Store. Tap Install and wait for it to download. The app requires iOS 12.0 or later, or Android 8.0 or later. On Android, the app runs on arm64-v8a, armeabi-v7a, x86, and x86_64 architectures, so it works on most modern devices.

Once installed, open the app. You will see a login screen with a field labeled "Server URL." This is where you enter your custom Mattermost server address. Do not skip this step. The app is designed to work with self-hosted servers, not just Mattermost Cloud. If you are using a managed Mattermost instance, you still need to provide the full server URL (e.g., https://mattermost.yourcompany.com).

Check your server version before proceeding. Mattermost mobile app v2.45.1 (released October 27, 2026) officially supports Mattermost servers running version 11.7.0 or later. If your server is older, you may experience connection errors or missing features. Update your server first if you are running an older version. The app will notify you if compatibility is an issue, but it is best to verify upfront.

One thing to note: the Mattermost mobile app is native to each platform. You are not using a web wrapper or PWA. This means better performance, offline message drafts, and native push notifications. However, it also means you need the current or near-current version of the app to stay compatible with new server releases.

Connect to a Self-Hosted Server: The Basics

Tap the Server URL field and enter your Mattermost server address. Include the full protocol: https://mattermost.yourcompany.com, not just mattermost.yourcompany.com. The app requires HTTPS for security. If your server only runs on HTTP (not recommended), the app will reject the connection.

Press "Connect." The app will attempt to reach your server and load the login form. If you see "Unable to reach your server" or a timeout, troubleshoot your network first. Verify that your firewall or reverse proxy allows connections from your mobile device. If you are testing on corporate WiFi, confirm that the WiFi network does not block outbound HTTPS. Test the URL from a browser on your phone first: open Safari (iOS) or Chrome (Android) and navigate to your Mattermost URL directly. If the browser can reach it, the network is not the issue.

Once the app connects, you will see the Mattermost login form. If your server uses single sign-on (SSO) or LDAP, the form will display the appropriate login method. If your server uses email and password, enter your credentials. Tap "Sign in."

If you see a certificate error ("This server could not prove it is mattermost.yourcompany.com"), you have an SSL/TLS configuration problem. This is common on self-hosted deployments with self-signed certificates or misconfigured reverse proxies. Go back to your server admin and verify: (1) your SSL certificate is valid and not expired, (2) the certificate matches your server's domain name, and (3) your reverse proxy (if using Nginx or Apache) is configured to pass the correct Host header. Do not tap "Trust" unless you understand the risk. A certificate error usually means you have a real problem to fix, not a warning to ignore.

Authentication on Mobile: SSO, LDAP, and MFA

The Mattermost mobile app supports the same authentication methods as the web client: email/password, LDAP, SAML single sign-on (SSO), and OAuth. If your server is configured for LDAP or SSO, the mobile app will use those methods when you tap "Connect" to your server URL.

If your server uses SAML or OpenID Connect, the app will redirect you to your identity provider's login page. Sign in there, and the app will complete the authentication. This flow is automatic; you do not need to configure anything on the mobile app itself. The server tells the app which authentication method to use.

Multi-factor authentication (MFA) is supported on mobile. If you have MFA enabled on your Mattermost account, you will be prompted to enter your second factor (usually a time-based one-time password from an authenticator app like Google Authenticator) after you enter your password. This is the same flow as on the web.

One key difference: the mobile app caches your login session on your device. Once you log in, the app will remain authenticated even if you close and reopen it. If you want to log out, go to Settings (gear icon in the bottom-right), scroll to the bottom, and tap "Log Out." This clears the session on your device. If your phone is lost or stolen, the person with physical access to your device can read your messages. Keep your device locked with a passcode or biometric lock.

Why Your Mobile Login Is Failing: Common Causes

Several common issues prevent mobile login on self-hosted Mattermost servers. Here is how to diagnose each.

SSL Certificate Error: The app says "The certificate for this server is invalid." This means the app cannot verify your server's SSL certificate. Causes: (1) self-signed certificate (common on test deployments), (2) certificate expired, (3) certificate domain mismatch (certificate says example.com, server is mattermost.example.com), or (4) reverse proxy not forwarding the correct Host header. Fix: Update your SSL certificate, or if you are on a test system, update it to a valid certificate. Ask your IT team to verify the reverse proxy configuration.

Connection Refused or Timeout: The app hangs on "Connecting to server..." or says "Could not connect to your server." Causes: (1) firewall blocks outbound HTTPS on port 443, (2) reverse proxy is not listening on the correct port, (3) Mattermost service is down, or (4) DNS cannot resolve your server's domain name. Fix: Test the URL in your phone's web browser first. If the browser loads your Mattermost login page, the network is fine and the issue is app-specific; try uninstalling and reinstalling the app. If the browser times out, the issue is network/firewall; contact your IT team.

Incorrect Username/Password: You see "Invalid credentials" after entering your email and password. Cause: You entered the wrong password, or your account is locked after failed attempts. Verify you are using the correct email address (case-sensitive on some LDAP systems). If you forgot your password, use the "Can't log in?" link on the login screen (if enabled on your server) to reset it. If your account is locked, contact your Mattermost admin.

LDAP or SSO Login Fails: You tap "SSO" or "LDAP" and see an error or blank page. Cause: Your server's LDAP or SSO configuration is broken, or the app cannot reach the identity provider. This is a server-side issue. Check your Mattermost server logs: go to System Console > Logs and look for LDAP or SSO errors. Common issue: the LDAP server is unreachable from your Mattermost instance. If using SSO, verify that your identity provider's redirect URI includes your Mattermost server's address.

"Unsupported Server Version": The app says your server version is not supported. Cause: Your Mattermost server is version 11.6.0 or older. Mattermost mobile app v2.45.1 requires server v11.7.0 or later. Upgrade your server. See the Mattermost releases page for your server's upgrade path.

Push Notifications: Hosted vs. Self-Hosted

Push notifications alert you when someone messages you, even if the app is closed. To send push notifications, Mattermost needs a service that can reach your phone while the app is not running. This is where the two options differ.

Option 1: Mattermost Hosted Push Notification Service (Recommended for Self-Hosted). You enable push notifications on your server, and Mattermost's cloud-hosted push proxy receives the notification and forwards it to Apple's APNs (iOS) or Google's FCM (Android). Your server sends the notification (without message content, just a flag that a new message arrived) to Mattermost's proxy. The proxy then sends it to the device. This method requires no infrastructure on your part. Downside: a third party (Mattermost) sees that you received a message. The message content is not sent to Mattermost, only a notification that a message exists.

Option 2: Self-Hosted Push Proxy. You run your own push notification service on your server or a separate instance. Your server sends notifications directly to your proxy, and your proxy forwards them to APNs/FCM. You control all the infrastructure, and no notification data leaves your network. Downside: you must set up and maintain the proxy service, obtain Apple and Google certificates, and troubleshoot delivery. This is complex and is rarely done in practice.

For most self-hosted Mattermost deployments, use Option 1 (Mattermost's hosted push proxy). It is free and requires no extra setup beyond enabling push notifications in System Console > Notifications. If you have strict data residency requirements or want zero third-party involvement, explore Option 2, but be prepared for configuration work.

If push notifications are not arriving, the first step is to check System Console > Notifications > Mobile Push > Send Push Notifications. It must be enabled. Next, verify your Apple and Google push certificates are configured (if using self-hosted proxy) or that Mattermost's hosted proxy is selected. If using the hosted proxy and notifications still do not arrive, check your firewall: your server must have outbound HTTPS access to push.mattermost.com.

Feature Parity: What's Available on Mobile

The Mattermost mobile app covers the core communication features: direct messages, channels, teams, file uploads and downloads, emoji reactions, and mentions. You can search message history, browse pinned messages, and set your status.

Not all web features are available on mobile. Advanced features like server administration, channel/team creation from the app (on some versions), and certain integrations or custom SlashCommands may be missing or limited. The best way to know if the feature you need is available is to test it on your phone after logging in.

One useful thing to know: if you need a feature that is not on mobile, you can still use it on the web. The mobile app and web client share the same data. Anything you do on mobile (send a message, create a channel) shows up on the web, and vice versa. So you do not have to worry that mobile is "limited." It is just a different interface for the same server.

For a full feature comparison, check the Mattermost mobile app release notes on GitHub (github.com/mattermost/mattermost-mobile). The release notes list new features and known issues in each version.

Scaling Mobile with Managed Hosting

If you are running Mattermost on your own infrastructure and finding that mobile setup is complex (managing SSL certificates, configuring push notifications, troubleshooting firewall issues), you might consider moving to a managed Mattermost hosting provider. A managed provider handles infrastructure, updates, SSL, and push notifications for you. Your team simply logs into the mobile app and works.

Opsily offers managed Mattermost hosting that simplifies mobile deployment. Your server is always up to date, SSL is handled automatically, and push notifications work out of the box. You get the same mobile app experience as self-hosted, but without the operational burden. If your team is growing and mobile access is important, this is worth evaluating.

For more on self-hosted options and trade-offs, see the Mattermost self-hosted guide. For a direct comparison of Mattermost against other team chat tools, check the Mattermost vs. Slack comparison.

Frequently Asked Questions

How do I update the Mattermost mobile app? Open the App Store (iOS) or Google Play (Android), go to your profile, and look for pending updates. Tap "Update" next to Mattermost. The app updates automatically on most phones if auto-update is enabled in your phone settings.

Can I use the Mattermost mobile app with Mattermost Cloud? Yes. Mattermost Cloud is a hosted instance managed by Mattermost. The app works the same way: enter your Mattermost Cloud URL and log in.

What if my server URL is behind a VPN? The mobile app will work as long as your phone can connect to the VPN and reach the server. If you are off the VPN and your server is not accessible from the public internet, the app will not connect. You will need to connect to your VPN first.

Does the mobile app work offline? Partially. The app caches your recent messages and channels. You can read cached messages and draft new messages while offline. Once you reconnect, drafted messages are sent. You cannot create new channels or perform other actions offline.

How do I delete my account from the mobile app? You cannot delete your account from the app. Go to the web client, click your avatar, select "Profile," and scroll down to "Danger Zone." You will see the option to deactivate or delete your account (if your server allows it). Contact your Mattermost admin if the delete option is not available.

Is the Mattermost mobile app free? Yes. The app is free to download and use. The cost depends on your Mattermost server (Cloud, self-hosted open-source, or self-hosted Enterprise).

Can I use the same Mattermost account on multiple devices? Yes. Log in on as many devices as you want using the same email and password. Each device maintains its own session and cache, but the messages and data are the same across all devices.

The Bottom Line

The Mattermost mobile app is straightforward to set up if your server is running version 11.7.0 or later and you have a valid SSL certificate. Enter your server URL, log in, and you are done. For self-hosted deployments, the main friction points are SSL configuration and push notification setup, both of which are manageable with basic server knowledge.

If your team relies heavily on mobile access and you want to eliminate operational overhead, managed Mattermost hosting removes these concerns. Start with the self-hosted guide to understand your current setup, then explore Opsily's managed hosting to see if it fits your team's needs.