Sound effects last 0.1–2 seconds. During that time, they must confirm the player's action, convey the physical properties of the object, and not become annoying after the hundredth repetition. This is especially acute in mobile games, where players perform hundreds of similar actions per session—every step, every hit, every UI click must sound natural and not irritate. We have been working on sound design for mobile games for over 5 years and know how to achieve this under strict memory and CPU constraints.
Why a single file per event is a mistake
If a step on a wooden floor is one WAV file, the brain notices the repetition after 8–10 steps. This is the "machine gun effect"—a term from game audio. The solution is a pool of variations: 4–6 variants of the same sound with small differences in pitch (±2 semitones), volume (±2 dB), and timing. In Unity, this is AudioSource.pitch = Random.Range(0.95f, 1.05f). In Wwise, a Random Container in shuffle mode.
The second level of variation is contextual variants: a step on metal sounds different than on stone. This requires a surface detection system: a raycast under the character returns the PhysicsMaterial, which selects the appropriate pool. Such architecture increases production time by 1.5–2 times, but completely eliminates monotony.
How sound effects are created for mobile games
Synthesis. For UI sounds, sci-fi effects, magic—synthesizers (Serum, Vital) and FM synthesis (FM8, DX7 emulation). An explosion in an arcade game is layering: low-end boom (sub via sine or pitchdown), transient (white noise through band-pass), tail (reverberation with decay 0.8–1.2 s). All three layers are synthesized or processed independently, then mixed. Synthesized sounds are 2–3 times cheaper to produce than Foley, but require careful tuning to sound organic.
Foley. Organic sounds—footsteps, impacts, creaks—are often recorded in a studio. A fist punch in an RPG: a real punch on a leather bag + a thin wooden crack + a synthetic transient in the high-mid (2–4 kHz for "bite"). Layering in a DAW (Reaper, Pro Tools, Nuendo), processing: EQ for body shaping, compression with fast attack to emphasize the transient, saturation for density. Foley gives a unique sound that cannot be exactly replicated by synthesis.
Libraries. Sonniss GDC Bundle (free, thousands of sounds), Boom Library, A Sound Effect—source material that is refined for the project. Taking "out of the box" without processing is bad practice: the sound will be recognizable (heard in 20 other games) and won't fit the overall palette. We refine each source—change pitch, cut, apply effects.
What are the technical requirements for sound on mobile platforms?
Final files: WAV, 44.1 kHz, 16-bit for most effects. Music stings and ambience—48 kHz / 24-bit. Stereo only for effects that will be used in 3D positioning or as music loops. Short UI sounds—mono, this halves memory.
Unity transcodes WAV to Vorbis (Android) and AAC (iOS) during build. For very short sounds (<200 ms), use Decompress On Load + PCM, otherwise decompression adds latency. For long ambient tracks—Compressed In Memory.
| Format |
Setting |
When to use |
| WAV |
44.1 kHz, 16-bit, mono |
Most SFX (footsteps, impacts, UI) |
| WAV |
48 kHz, 24-bit, stereo |
Ambient, music stings |
| PCM |
Decompress On Load |
Ultra-short (<200 ms) |
| Vorbis/AAC |
Compressed In Memory |
Long backgrounds, looped tracks |
Normalization to -16 LUFS (integrated) is mandatory before delivery. Peak limit— -1 dBTP. Without this, the mix on the device becomes uncontrollable. Compare: unprocessed sounds can differ in volume by 6–10 dB, ruining the game balance.
What is included in an SFX delivery?
All SFX as named WAV files with descriptions in the specification. If the project uses Wwise or FMOD—additionally configured events with variations inside the middleware. If Unity—prefab AudioClip with import settings or AudioMixer group. We also provide:
- a full checklist of used sources (libraries, recordings, synthesis);
- documentation on the variation system and contextual selection;
- a guarantee to replace any sound without additional charge within two weeks after delivery.
Approximate timelines
A standard set of 30–80 effects takes 1 to 2 weeks. The budget is determined individually after analyzing the game's sound map—contact us for an estimate.
To order sound effects for your game, contact us—we will evaluate your sound map and offer the best option. Request a demo set of varied SFX—we'll demonstrate quality on your scenes.
How to Choose a Camera Approach on Mobile Platforms?
Apps where users capture, listen, or watch are technically among the most demanding. We deal with this every day. Not because of API complexity, but due to hardware differences: on a flagship, the camera works perfectly; on a budget device with a non-standard Camera HAL, artifacts and failures occur. On iOS, stabilization differs between generations. Platform differences account for 80% of all media development complexity. Our experience: 7+ years in mobile media and over 40 implemented projects with camera, audio, and video.
What are the Differences Between CameraX, Camera2, and AVFoundation?
On Android, the Camera2 API was long the only adequate choice for custom cameras. It is a low-level API with CaptureRequest, CameraCharacteristics, ImageReader — powerful but verbose. Even a preview with correct aspect ratio and proper orientation takes several hundred lines of code.
CameraX (Jetpack) is a wrapper around Camera2 with automatic device adaptation. Preview, ImageCapture, ImageAnalysis, VideoCapture — four use cases that can be combined. It handles orientation, aspect ratio, and lifecycle for you: bind to a LifecycleOwner and forget about closing the camera when the app goes to background. In recent versions, CameraX includes Extensions API for bokeh, night mode, HDR — using native manufacturer algorithms via a unified interface.
When is Camera2 needed directly?: RAW capture via ImageFormat.RAW_SENSOR, manual control of ISO/shutter speed/focus, or when CameraX Extensions API is not supported and a custom ML pipeline in ImageAnalysis is required.
On iOS, AVFoundation is the only path for a custom camera. AVCaptureSession with AVCaptureDeviceInput and the required output (AVCapturePhotoOutput, AVCaptureVideoDataOutput, AVCaptureMovieFileOutput). For real-time video processing — AVCaptureVideoDataOutput + CVPixelBuffer in captureOutput(_:didOutput:from:) on a background queue. This is where CoreML models receive frames for inference.
A typical mistake with AVFoundation: configuring the session on the main thread. beginConfiguration() / commitConfiguration() should be called on a background thread. Otherwise, the preview freezes, and the user sees a frozen UI. This mistake appears in 70% of the projects we have audited.
Why is AudioFocus Critical for Android Apps?
Audio on mobile platforms requires correct management of the sound lifecycle. AudioFocus is a coordination mechanism between apps. AudioManager.requestAudioFocus() with OnAudioFocusChangeListener. If you don't handle AUDIOFOCUS_LOSS_TRANSIENT (pause) and AUDIOFOCUS_LOSS (stop) — your app will play over a phone call. That guarantees a bad review on Google Play. Android Developer Guide: AudioFocus
On iOS, AudioSession categories define behavior: playback — for players (continues playing when screen is locked), record — for recording, muting other sources, playAndRecord — for voice messages. Wrong category — the app mutes the user's background music on start.
AVAudioEngine — modern API for audio processing: a graph of nodes (mixers, equalizers), taps for buffer capture. For real-time speech — SFSpeechRecognizer + inputNode.installTap.
On Android for recording with noise suppression — NoiseSuppressor.isAvailable() + create(audioRecord.audioSessionId). Works not on all devices, need a fallback.
Video: Playback and Streaming
ExoPlayer (Media3) — standard for Android. Supports HLS, DASH, SmoothStreaming, progressive playback. DefaultTrackSelector with Parameters allows manual or adaptive quality selection. DRM via DefaultDrmSessionManager with Widevine L1/L3.
Almost everyone faces this problem: ExoPlayer in RecyclerView with fast scrolling. Need a PlayerPool — a pool of reusable players. Without a pool, each new instance creates a MediaCodec instance, which is expensive and leads to MediaCodec$CodecException: Error -19 on some Android 10 devices with more than 3 simultaneous instances.
AVPlayer / AVPlayerViewController on iOS — for playback. For custom UI — AVPlayerLayer + custom controls. HLS works natively via AVPlayer(url:) with m3u8. FairPlay DRM requires a server part: AVContentKeySession, CKC response from KSM server, resource delegate.
For Flutter — video_player as a base layer, chewie for UI. For serious tasks — a platform channel to native ExoPlayer/AVPlayer (due to DRM and subtitles).
| Protocol |
Latency |
Application |
| RTMP |
2–5 sec |
Streaming to YouTube/Twitch |
| HLS |
6–30 sec |
VOD, broadcast |
| DASH |
6–30 sec |
VOD with adaptive bitrate |
| WebRTC |
< 500 ms |
Video calls, P2P |
| SRT |
1–4 sec |
Professional streaming |
WebRTC on mobile — via native frameworks or flutter_webrtc. The real complexity is not in the protocol itself, but in signaling and TURN servers. Without TURN, clients behind symmetric NAT won't establish a connection — that's about 15–20% of traffic. Coturn is the standard open-source server.
RTMP publishing on mobile: LFLiveKit for iOS, HaishinKit as a more modern alternative. On Android — rtmp-rtsp-stream-client-java or via FFmpeg with JNI. The latter gives maximum flexibility but increases the binary by 10–15 MB.
Media Processing: Compression and Transcoding
ProRes video can take up to 6 GB/minute. Compression is needed before upload. On iOS — AVAssetExportSession with a 1920×1080 preset or custom AVVideoComposition. VideoToolbox for hardware H264/HEVC encoding — faster and more battery-efficient.
On Android — MediaCodec directly or Transformer (Media3) — a high-level API for transformations (trimming, resizing, effects via GlEffectsFrameProcessor). For images — BitmapFactory.Options.inSampleSize for downsampling, Glide / Coil for caching. Coil on Coroutines fits well with Compose. Loading a 12 MP original into an ImageView of 200×200dp — a classic OutOfMemoryError on devices with 2 GB RAM.
How to Implement Streaming on Mobile Devices: Step-by-Step Plan
- Define requirements: target latency, number of concurrent users, need for P2P.
- Choose protocol and stack: WebRTC for video calls, RTMP/HLSLive for broadcasting.
- Set up signaling (SIP, WebSocket, MQTT) and TURN server.
- Implement publishing/viewing via native API or cross-platform plugin.
- Test on real devices with different cameras and network conditions.
- Optimize bitrate and resolution based on bandwidth.
Typical Mistakes in Media Feature Development
- Configuring AVFoundation session on the main thread.
- Missing AudioFocus Loss handling on Android.
- Ignoring
MediaCodec limitations on cheap devices.
- Using emulator for camera tests — emulator does not replicate HAL issues.
- Memory leaks when recreating media players without a pool.
What is Included in the Work
| Deliverable |
Description |
| Requirements analysis |
Stack selection, priorities, test devices |
| Design |
Architecture, data flow diagrams, API selection |
| Implementation |
Code using chosen tools |
| Backend integration |
GraphQL/REST, DRM, WebRTC signaling |
| Testing |
On real devices (at least 5 models) |
| Documentation |
API documentation, build instructions |
| Post-release support |
1 month incident support, team training |
Development Process for Media Functionality
Complexity is non-linear: basic video playback — 1–2 days, custom camera with frame processing and streaming — 3–5 weeks. We start by clarifying requirements: DRM, formats, minimum OS, background mode support. Testing on real hardware is mandatory — the emulator does not replicate Camera HAL, hardware codec, and AudioFocus issues. Minimum set: latest iPhone, iPhone SE, flagship Samsung, budget Android, Android Go (if target audience is developing markets).
Timeline estimate: from 5 business days (basic playback) to 8 weeks (complex camera with streaming and DRM). Cost is calculated individually after analyzing your requirements — contact us for a consultation.
Our service: "Mobile Media Integration" — this is our expertise. Every project starts with an audit of the current implementation, identifying bottlenecks, and proposing an optimal stack.
Commercial signals: order an audit of your media functionality, get a free consultation from an engineer.
