Unda

Unda Support

Updated September 23, 2026

Answers to common questions about Unda, the speaker cleaner and audio test kit for iPhone and iPad. Can't find what you need? Email support@apphunt.app.

How water eject works

Unda plays a low tone at about 165 Hz, the frequency at which a phone speaker moves the most air. The vibration shakes trapped droplets loose and helps push them out through the grille — the same trick as the well-known Water Eject shortcut and the Water Lock feature on Apple Watch. Higher frequencies in the Dust Removal program help loosen dust and lint.

The tone is tuned to your device: 165 Hz on most iPhones, 175 Hz on compact iPhones and 155 Hz on iPad. Sound only reaches water in the speaker grille: it can't dry the inside of the phone, repair a damaged speaker or undo water damage.

Before you start

• Take the phone out of a thick case and wipe the grille.
• Turn the volume all the way up. Unda asks for this and shows a slider.
• Point the speaker down so gravity helps. For the earpiece program, hold the top of the phone facing down.
• Disconnect headphones, AirPods and Bluetooth speakers so the sound plays from the phone.
• To clean AirPods or headphones instead, keep them connected, take them off, lay them mesh-side down and run the Headphones program. Never wear them while it plays.

Which program to pick

Lengths are for Normal. Choose Light, Normal or Intensive (higher intensity plays louder and longer) and run 2–3 cycles for stubborn water; Unda pauses a few seconds between cycles. If the speaker still crackles after four cycles, it may be physically damaged, and a repair shop is the next step.

After a cleaning

When a program finishes, wipe the grille with a dry cloth, tap Play test sound and answer Sounds clearer or Still muffled. Your answer is saved in the history on the Clean tab, so you can see whether repeated cycles help. Wait a few hours before charging a phone that was wet.

Speaker and microphone tests

• Frequency sweep plays every frequency from 20 Hz to 20 kHz in 15 seconds. A healthy speaker sounds even, without crackle or dropouts.
• Stereo test plays the left and right channels separately, with a 440 Hz tone or a 55 Hz bass tone. iPhones play stereo through the bottom speaker and the earpiece.
• Earpiece plays only through the call speaker. Hold the phone to your ear.
• Microphone records four seconds and plays them back. A muffled or quiet recording points to a clogged microphone grille.
• Headphones & external plays through whatever is connected right now.

Tone generator

Swipe up or down, use the slider or the ±1 and ±100 buttons to set any frequency from 1 Hz to 25 kHz. Choose left, right or both channels, set the volume, turn on Auto sweep to glide up to 20 kHz and back, or set an auto-stop timer. The sine wave is free; square, triangle and saw waves come with Premium. Presets cover the 165 Hz water eject tone, tuning A, hearing checks and ultrasonic frequencies. Frequencies above 17 kHz are inaudible to most adults but still play, so keep the volume moderate with headphones.

Noise meter

The Meter tab shows an A-weighted level in dBA, the dominant frequency, minimum, average and maximum, and a history chart. Phone microphones aren't certified instruments, so the reading is an estimate: tap the calibration button and match it to a reference meter if you have one (the offset goes from −30 to +30 dB). dB Camera (Premium) takes a photo stamped with the level, date and time, and optionally your city.

Siri, widgets and reminders

• Siri: say “Eject water with Unda” or “Clean my speaker with Unda”. The app opens and starts the program.
• Widgets: touch and hold the Home Screen or Lock Screen, add the Unda widget, and tap it to start Water Eject.
• Weekly reminder: turn on Weekly care reminder in Settings for a nudge on Sunday evenings.

Unda Premium

Unda is free to download. Water Eject, Deep Clean, Dust Removal, Turbo, Earpiece, Headphones, Weekly Care, every test, the tone generator and the noise meter are free with no limits. Unda Premium adds the Full Care and Vibration programs, dB Camera, extra waveforms and the hearing-check and ultrasonic presets.

Prices are in US dollars. The App Store shows the price in your currency before you buy.

Buy Unda Premium

Open Settings → Unlock Unda Premium, or tap any feature marked PRO. Choose a plan and confirm with Apple. Apple handles the payment and charges your Apple Account.

Restore a purchase

On a new device or after reinstalling Unda, tap Restore purchases in Settings or at the bottom of the Premium screen. Use the Apple Account you bought Premium with.

Cancel a subscription

Apple manages subscriptions. On your iPhone, open Settings, tap your name, then Subscriptions → Unda, and tap Cancel Subscription. Cancel at least a day before your subscription renews or your free trial ends to avoid being charged. Deleting the app doesn't cancel a subscription. For a refund, contact Apple at reportaproblem.apple.com.

Safety

Unda keeps the output within the safe range of a phone speaker. Don't hold the phone to your ear while a cleaning program runs, never wear headphones while one plays, don't put a wet phone in rice, and don't blow compressed air into the grille. Unda can't repair physical damage and isn't a certified measuring instrument.

Contact support

Email support@apphunt.app with “Unda” in the subject. Tell us your iPhone model, your iOS version, your Unda version (Settings, at the bottom) and what you expected to happen. We usually reply within one business day.