Larix Broadcaster for iOS
iOS app for capturing and streaming on iPhone and iPad
Encoding and streaming features
The core of our tools is Larix streaming library.
Key content streaming features include:

- SRT publishing in Push (Caller), Listen and Rendezvous modes
with streamid, latency, maxbw parameters and more via libsrt version 1.5.0. - RTMP publishing, including SSL support (RTMPS)
- Enhanced RTMP spec is supported to deliver HEVC via RTMP (premium)
Watch How to stream HEVC to YouTube via RTMP video tutorial for Larix Broadcaster - New: Zixi output
Use Larix to deliver live streams via Zixi protocol.
See more details below. - NDI®|HX2 output (premium feature)
You can use your device as NDI source, see details below. WebRTC output with WHIP signaling. (premium feature)
See more details below.- RIST protocol Push mode support: RIST Main and Simple Profile, librist 0.2.7.
Use "rist://ipaddress:port" for new connection URL. - RTSP publishing, including SSL support (RTSPS).
- Multiple simultaneous connections to several destinations. (premium feature for 3+ connections)
- Pause and Stand-by modes, see description below.
- Talkback for Larix Broadcaster allows getting audio return feed from studio. (premium feature)
- Adaptive bitrate (ABR) video is supported via logarithmic descend, ladder ascend, hybrid approach and variable FPS.
Read respective question in Larix FAQ to learn more technical details. - Insert SEI time metadata and specify NTP server, this allows synchronizing streams on server side.
(premium feature)
Use Advanced menu to operate it. Watch video tutorial to see it in action.
Minimum supported iOS version is 12.
Codecs:
Video is encoded with interleaved H.264/AVC everywhere.
H.265/HEVC is available on supporting devices.
This includes transmission over Enhanced RTMP which allows publishing HEVC into YouTube, with HDR on supported devices.
HEVC is a premium feature
Audio is encoded with AAC everywhere except WebRTC. In WebRTC, the codec is Opus.

Larix supports live streaming via Zixi protocol from iPhone and iPads.
- AVC/H.264 and HEVC/H.265 codecs are supported
- SEI timestamps
- Change bitrate according to network conditions
- Use Wifi + Cellular bonding
- FEC control and other specific parameters

NDI®|HX2 output (premium feature)
You can turn your mobile device into NDI source
for just $19.99 per month in-app subscription:
- Output streaming via NDI®|HX2
- AVC/H.264 and HEVC/H.265 codecs are supported
- Preview stream support
- Discovery Server and connection metadata
- Handle zoom from NDI Studio Monitor
- NDI SDK 2023-04-10 r134150 v5.5.4
WebRTC output support (premium feature)

- WHIP signaling is used for communication with server side.
- H.264/AVC video and Opus audio encoding.
- Multiple simultaneous connections via any protocols.
- Tested with Cloudflare Stream, Dolby.io and Nimble Streamer.
- Watch Ingesting WebRTC from Larix Broadcaster into Nimble Streamer, video tutorial featuring iPhone low latency output via WHIP.
- Read Broadcasting Mobile Native WebRTC Streams by Dolby.io showing Larix WebRTC usage example.
Larix Grove format allows you easily distribute your connection and encoder settings via deep links and QR codes.
Full support for Facebook Live, YouTube Live, Twitch, Wowza Streaming Cloud, Amazon Interactive Video Service, Periscope, Dacast, Akamai, Limelight and other online services. All popular authentication methods are supported. Check docs reference for setup instructions.
Image, audio and other features
You can use streaming capabilities for free using our fully-functional Larix Broadcaster apps.
Besides encoding and streaming features, Larix Broadcaster uses full power of mobile devices:
- Landscape and portrait various modes support with device dynamic orientation.
- "Always vertical" and "Always horizontal" modes
- Front and back cameras with hot switch.
- Dolby Vision HDR support on iPhone 12 and beyond along with certain iPad models.
Enabled in Settings / Video / HDR video menu.
(premium feature) - iPhone 11 Dual/Triple camera system support, including wide-angle and telephoto camera
- Multi-camera capture with picture-in-picture and side-by-side. Supported on iPhone XR, iPhone XS, iPhone XS Max, iPad Pro (3rd generation) and later devices.
To use this option, go to Settings -> Capture and encoding -> Video -> Multi-camera capture. - Center stage on latest iPads, enabled as described here.
- 4K streaming support on latest iOS devices.
- Video+audio, video only and audio only modes.
- Pause the stream: when streaming, long tap on Start will pause the stream without disconnecting it.
Video track will contain a black screen, audio track will contain silence.
A separate set of overlays can be mapped onto pause. - Stand-by mode: when stopped, long tap on Start will start stream in pause mode, waiting to start with the camera image.
A separate set of overlays can be mapped onto stand-by. - Image overlays video tutorial shows overlays for streaming as well as pause and stand-by modes.
- Input audio gain control
- Audio-only capture mode: disable preview, stream from background, no video in output stream.
Watch Audio-only background streaming video tutorial. - Fixed FPS can be selected from the list of supported values.
- Auto Focus Lock - long press anywhere in the preview, and AF is locked until you tap to re-focus.
- Recording to MP4 and saving screenshots with iCloud Drive and Photo Library support and files separation.
- Use custom parameters (resolution, codec etc) for recording.
- Pinch-to-zoom, including iPhone 11 multi-camera.
- Bluetooth audio.
- Flash light support.
Overlays support:
- Image layers with external URL and local images;
- Web widgets;
- Text and HTML widgets;
- GPS-based data like coordinates, speed and more
- Timestamp support as defined on unicode.org, e.g. <%date('MMM dd, HH:mm:ss', en_US) %>
- Assign layers for all mode: streaming, pause and stand-by;
- Image overlays video tutorial shows overlays for streaming, pause and stand-by modes.
Join Beta program in TestFlight using this link to obrtain the latest version and get updates befopre their official release.
This tutorial shows the setup of outgoing connections in Larix Broadcaster.
Documentation and FAQ
- Visit documentation reference page to learn more about Larix apps setup and usage.
Docs page has a huge number of setup instructions and tutorials.
Also watch our YouTube playlist with various video tutorials. - Larix Broadcaster FAQ has most popular questions about mobile streaming technologies.
- Best practices for Larix Broadcaster production deployment for live streaming from mobile devices.
- Contact our helpdesk regarding our mobile technologies.
Larix Screencaster free app

iOS allows capturing the screen of user device, so Larix Screencaster uses streaming capabilities to capture the screen, encode and stream it.
However, iOS puts some limitations on audio. If you stream your screen, you can only use your microphone. If currently opened application supports ReplayKit, then you'll be able to stream its sound.
Read this article for setup details or refer to Apple's support article or support video with our own setup video.
This product uses SRT library distributed under MPL-2.0 license.
This product uses librist library distributed under BSD 2-clause "Simplified" license.
iOS Larix Broadcaster uses Scrollable Segmented Control distributed under MIT license.
This product includes software developed by the OpenSSL Project for use in the OpenSSL Toolkit.
Larix Broadcaster uses Pion implementation of WebRTC API. Special thanks to Sean DuBois and all Pion contributors.