Smart Home Multimedia Mobile App Development
Multimedia management in a smart home — TVs, AV receivers, streaming devices, multi-room audio. App task: unified remote control for all home equipment, including audio zone creation and content synchronization.
AV Equipment Control Protocols
HDMI CEC — control TVs via HDMI bus. Via Pulse-Eight adapter or built-in CEC in Raspberry Pi can send commands (on/off, input switch, volume) from mobile via MQTT bridge. No direct API from app — only via backend with CEC adapter.
IP Control — most modern AV receivers Denon, Yamaha, Onkyo support Telnet or HTTP on ports 23 or 80. Commands via socket: MVUP, MVDOWN, SICD (input switch). On Flutter: dart:io Socket. On React Native: react-native-tcp-socket. No public SDK — only protocol docs for each manufacturer.
Sonos — REST API via local network. Sonos HTTP API on port 5005 (via sonos-http-api bridge) or official Sonos Platform API (OAuth2, cloud). Manage playback (play, pause, next), volume, multi-room grouping. Event subscription via polling or UPnP SUBSCRIBE.
Apple TV — MediaRemoteTV protocol (MRP) or HomeKit. Via HomeKit on iOS can control Apple TV without Apple TV SDK. HMAccessory with HMServiceTypeTelevision. Without HomeKit — via ATV Remote framework or tvOS Companion Link (needs pairing).
Chromecast/Google TV — Google Cast SDK for iOS and Android. Official google_cast Flutter plugin unstable — commonly use flutter_cast_framework or native code via Platform Channel.
Kodi — JSON-RPC API, http://{host}/jsonrpc. Full control over media library, playback, plugins. Great option for home media centers.
Multi-room Audio
Play one audio source in multiple rooms simultaneously — technically non-trivial due to synchronization.
Sonos — internal synchronization between speakers. API: POST /zones/{roomName}/group to merge zones. Delay between speakers < 1ms. Group control from app — standard.
Snapcast — open-source solution for synchronized multi-room audio. Clients on Raspberry Pi in each room. Server REST API: GET /jsonrpc with methods Server.GetStatus, Client.SetVolume, Group.SetMute. On Flutter: http requests to Snapcast server via home network.
AirPlay 2 — iOS native. AVRoutePickerView for AirPlay 2 receiver selection. Multiple receivers simultaneously via AVAudioSession.setPreferredOutputNumberOfChannels. On third-party devices (Raspberry Pi) — Shairport Sync with AirPlay 2 support.
Universal Remote: IR Control
IR Blaster devices (Broadlink RM4, BestCon RM4C) — send IR commands to TVs and AC units without Wi-Fi on the device. Broadlink Python SDK (broadlink) well documented. On Node.js server: const device = new broadlink.genDevice({type: 0x6039, ...}) → device.sendCode(irCode).
IR code database: IRDB (github.com/probonopd/irdb), Pronto Hex format. On Flutter show brand and model list — user selects their TV, load codes from database.
Problem: IR codes differ for each TV model. Need database of thousands of models or "learning" function — record existing remote via Broadlink.
Streaming Service Integration
Deep link to streaming platform via app: intent://www.netflix.com/watch/...#Intent;scheme=https;package=com.netflix.mediaclient;end (Android) or nflx://www.netflix.com/watch/... (iOS). Launch specific content on TV from mobile app.
Via Chromecast: Cast SDK lets launch Netflix/YouTube on Chromecast and start playback via RemoteMediaClient.load() with MediaInfo containing contentId.
Timeline
Basic control of one system (Kodi, Sonos or AV receiver from one brand) — 3–4 weeks. Universal remote with IR, multi-room audio, multiple protocols, zones — 2–4 months. Cost depends on equipment set and offline work requirements.