PocketMIDI: MIDI Keyboard

PocketMIDI is a free, low-latency MIDI synthesizer and piano app for Android, built for live performance.

Whether you're connecting a USB MIDI keyboard on stage or playing the on-screen piano keyboard, PocketMIDI delivers studio-quality sound with a latency target of under 40 ms — fully offline, no ads, no tracking.

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INSTRUMENTS

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• Grand Piano — Salamander Grand Piano V3 (Alexander Holm), 30 root notes spanning the full 88-key range (A0–C8), OGG Vorbis samples.

• Strings — rich, expressive orchestral strings with natural attack and release.

• Dark Pad — lush, atmospheric pad for ambient and cinematic performance.

• Synthesizer — built-in digital synthesizer with PolyBLEP waveforms (sine, saw, square, triangle), full ADSR envelope, and a state-variable filter.

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USB MIDI KEYBOARD SUPPORT

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Connect any class-compliant USB MIDI keyboard via OTG adapter. PocketMIDI automatically detects the device and routes MIDI note on/off and sustain pedal (CC64) events directly to the audio engine with minimal overhead.

• Auto-launch when a keyboard is connected (optional)

• Full polyphony: up to 96 simultaneous voices (64 sample + 32 synth)

• Velocity sensitivity and sustain pedal support

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ON-SCREEN KEYBOARD

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• 2-octave multi-touch piano keyboard (C3–C5)

• Up to 10 simultaneous touches for polyphonic playing

• Velocity-sensitive: tap position affects note velocity

• Amber highlight on pressed keys

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SYNTH EDITOR

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When the Synthesizer instrument is selected, a full synth editor is available:

• Waveform selector: Sine, Saw, Square, Triangle

• ADSR envelope: Attack (1 ms–4 s), Decay (1 ms–4 s), Sustain (0–100%), Release (1 ms–8 s)

• Low-pass filter: Cutoff and Resonance

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PRESETS

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• Save your favourite instrument and synth settings as named presets

• Load presets instantly during a performance

• Export all presets to a JSON file and share via any app

• Import presets from a JSON file

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METRONOME

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• Built-in click track: 20–300 BPM

• Time signatures: 2/4, 3/4, 4/4, 6/8, 7/8, 5/4

• Visual pulse animation on the status bar

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PERFORMANCE & SETTINGS

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• Real-time performance monitor: active voices, buffer size, sample rate, estimated latency, buffer underruns

• Fully offline — no internet connection required, no ads, no tracking

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TECHNICAL

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• Audio engine: Oboe 1.9.0 (AAudio with OpenSL ES fallback)

• Audio buffer: ~4 ms @ 192 frames, 48 kHz

• Automatic stream restart with exponential backoff

• Minimum Android 8.0 (API 26)

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ATTRIBUTIONS

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Salamander Grand Piano V3 samples by Alexander Holm are used under the Creative Commons Attribution 3.0 license (CC BY 3.0). No modifications were made to the samples.

https://creativecommons.org/licenses/by/3.0/