How to Set Up Moblin with an SRTLA Relay (2026 Guide)

Moblin turned iPhones into serious IRL cameras: native SRT and SRTLA output, adaptive bitrate and a clean interface. But the app is only half of the chain — the other half is the receiving server that bonds your connections and hands stable video to OBS. This guide walks through connecting Moblin to an SRTLA relay end to end.

What you need before starting

• ▸An iPhone running Moblin (free on the App Store)
• ▸An SRTLA relay endpoint — from a provider like PerHost or self-hosted via BELABOX tools
• ▸Your OBS (or a cloud OBS) ready to receive the feed
• ▸Ideally two networks on your phone: cellular plus WiFi or a second SIM

Step 1 — Get your SRTLA endpoint

When you create an account with a relay provider you receive three values: a host, a port and a streamid. Together they form a URL like srtla://host:port/streamid. Keep these private: anyone with them can inject video into your stream.

Step 2 — Configure the connection in Moblin

Open Moblin, go to Streams, add a new SRTLA connection and paste your srtla:// URL. Set your target bitrate conservatively at first — 3 to 6 Mbps is realistic for bonded urban 4G — and leave adaptive bitrate enabled so the app can react to network changes instead of flooding the link.

Step 3 — Receive the feed in OBS

The relay re-emits your stream as an SRT source. In OBS add a Media Source, check the option for local off, and paste the srt:// watch URL your provider gives you. Give it a second: you should see your camera appear with sub-second latency.

Step 4 — Test like you'll actually stream

• ▸Walk the real route you plan to cover, not just the sidewalk outside
• ▸Toggle WiFi off and on mid-stream to confirm bonding absorbs the switch
• ▸Check per-link stats in your dashboard to spot a weak SIM before showtime
• ▸Configure an OFFLINE fallback scene in OBS for total coverage loss

Common mistakes

• ▸Setting max bitrate higher than your weakest link can sustain
• ▸Sharing your streamid in screenshots or streams
• ▸Forgetting that VPNs on the phone can break bonding paths
• ▸Testing on WiFi only and discovering cellular issues during the event