Tone Generator is the most accurate audio frequency generator and sine wave oscillator for Android. Generate pure tones from 1 Hz to 22 kHz with sine, square, sawtooth, and triangle waveforms — replace expensive lab signal generators with the phone you already carry.
Whether you're an audio engineer calibrating speakers, an electronics hobbyist testing circuits, a HAM radio operator validating audio chains, a musician tuning instruments to specific Hz, or a hearing test administrator generating reference tones — Tone Generator turns your phone into a professional signal generator.
▶ MAIN FEATURES
• Sine, square, sawtooth, triangle waveforms
• Frequency 1 Hz – 22 kHz with 0.1 Hz precision
• Volume control (0% to 100%)
• Stereo L/R balance and independent channel control
• Sweep mode (frequency rises/falls over time)
• Mute/unmute hold mode
• Visual waveform display
• Dark mode for studio use
• Works fully offline — no data plan required
• No microphone permission needed (output only — total privacy)
▶ WHY TONE GENERATOR+
Most "tone apps" max out at 16 kHz with limited waveform choice. Tone Generator goes to 22 kHz (full audible range plus dog whistle frequencies), with all four standard waveforms (sine, square, sawtooth, triangle), 0.1 Hz precision, sweep mode for response testing, and stereo balance for left/right channel checks. This is the same toolset audio engineers pay $300 for — built into your phone.
▶ HOW TO USE
1. Pick a waveform (sine is the cleanest pure tone)
2. Set frequency with the slider or numeric input (e.g., 440 Hz for A4 musical note)
3. Adjust volume to a safe level (start low for hi-freq tones)
4. Tap Play — pure tone outputs immediately
▶ WHO USES TONE GENERATOR
• Audio engineers calibrating speakers and headphones (sweep test)
• Hearing test administrators (1 kHz reference tone)
• Musicians tuning instruments to specific Hz (440 Hz A4, 261 Hz C4, etc)
• HAM radio operators testing audio chains and SSB modulation
• Electronics hobbyists testing op-amp circuits and filter response
• HVAC technicians demonstrating frequency masking principles
• Speaker installers checking phase alignment between drivers
• Acoustic researchers generating test tones for room measurement
• Video producers generating reference tones for sync and EQ
• Pet owners testing dog whistle frequencies (15-22 kHz, beyond human hearing)
▶ FAQ
Q: How accurate is the frequency? A: 0.1 Hz precision, generated by 48 kHz audio engine.
Q: Why does the high frequency tone sound quiet? A: Phone speakers roll off above ~16 kHz; use headphones for full range.
Q: Can I save presets? A: Quick save coming soon. For now, presets at 440/1000/4000 Hz.
Q: Does it use the microphone? A: No — output only. No microphone permission needed.
Q: Is this safe for hearing? A: Loud high-frequency tones can damage hearing. Always start at low volume.
⚠ WARNING: Loud high-frequency tones can damage hearing. Always start at low volume and increase gradually.
▶ COMPATIBILITY
Works on Android 7.0 and above. No microphone permission required. Works with phone speakers, wired headphones, Bluetooth audio, and external USB audio interfaces.