HearRelay

What HearRelay is

HearRelay is an iPhone / iPad sound monitor that lets you hear what a device’s microphone picks up — live, through headphones or on another Apple device (subtitle: Sound Monitor for Baby & Noise Check). The main uses are (1) a baby monitor and (2) tracking down the source of a noise (noise check).

• Pairing works only across devices on the same Apple Account and the same Wi-Fi (local network). It never works over the internet — there is no internet relay or cloud path (this is a security and privacy design decision, not a missing feature).
• There is no data collection, and audio is never sent to a server (end-to-end encryption).

Glossary — End-to-end encryption: encryption where only the sending and receiving ends can read the content. Local network: a nearby network such as your home Wi-Fi. iCloud Key-Value storage: a small settings area in your Apple Account space (used here for pair discovery). Live monitoring: hearing a microphone’s sound in real time, on the spot.

Three modes

• Standalone — on the same device: microphone → headphones. Listen to your own surroundings.
• Pair (Send) — stream this device’s mic audio to another Apple device on the same Wi-Fi.
• Pair (Listen) — receive another device’s mic audio and listen through your own headphones.

The two pair modes are intentionally limited to the same Apple Account and the same Wi-Fi / local network. Devices on the same Apple Account connect with one tap and no extra approval, and the sending device shows a “sending audio” indicator.

Key features

• End-to-end encryption — audio between paired devices is encrypted in transit. It is never sent to our servers (we operate no servers).
• Same Apple Account + same Wi-Fi only — it does not work over the internet (a design decision).
• No data collection — no tracking, no analytics, and no ad SDKs.
• Headphone output required (feedback prevention) — supports wired (3.5mm / USB-C / Lightning), USB DAC, and Bluetooth headphones. It refuses to start while output is on the built-in speaker / earpiece (to prevent feedback).
• Standalone fixes the mic to the built-in microphone — to keep Bluetooth from switching to low-bandwidth HFP. Input is the built-in mic; only output is Bluetooth.
• Background continuation — monitoring / relaying continues while the screen is locked.
• Live Activity (Dynamic Island) — shows the status (including the current output route name) on the Lock Screen and elsewhere. Due to an OS limit, there is a maximum display time (about 8 hours).
• Noise suppression — echo cancellation is always on (automatic gain control is off).
• Six languages — Japanese / English / French / Spanish / Brazilian Portuguese / Simplified Chinese.
• Accessibility — VoiceOver and Dynamic Type supported.

Recording (local recording)

On the listening side (Standalone / Pair Listen), you can record the monitored sound to the device as AAC .m4a.

• It starts only on your explicit action. The first time, a consent screen appears before recording (no secret recording, eavesdropping, surveillance, or recording without consent; obtaining lawful consent is your responsibility; it is not a safety/medical device).
• It is never uploaded, never sent to our servers, and there is no export / share feature. A recording cannot leave the device.
• It is automatically deleted after 24 hours by default. Saving disables auto-deletion, and the recording stays on the device until you delete it. The list shows a countdown of the remaining time.
• While recording, an in-app indicator and a stop button are shown, and the app respects the iOS system microphone indicator. On playback, silent passages are skipped automatically (the app only detects “sound present” segments on the device).
• It does not perform voiceprint extraction, speaker identification, transcription, biometric identification, or cloud analysis.

Getting started (the three modes)

• Standalone — connect headphones and start. This device’s mic audio plays through your headphones (it cannot start with built-in speaker output — feedback prevention).
• Pair (Send) — on the device you place in the spot you want to monitor, start “Send.” It streams audio to the listening side on the same Apple Account.
• Pair (Listen) — on the device in your hand, start “Listen” and pick the other device from the pair candidates; its mic audio plays through your headphones.

Quick help

“No devices found” when pairing Both devices must meet all of: the same Apple Account, the same Wi-Fi (same subnet), iCloud enabled, and Microphone and Local Network permissions granted to HearRelay. If those are met, refresh the pair-candidate screen or restart the app on both devices.

Audio cuts out / stutters Move closer to the Wi-Fi router or switch to 5 GHz. A Bluetooth headphone with a weak signal can cause dropouts (try wired or a different model). Large downloads or video calls on the same Wi-Fi affect real-time audio.

AirPods sound quality is low in Standalone mode This is by design. To keep Bluetooth from switching to low-bandwidth HFP, the mic input is fixed to the built-in microphone. Use the built-in mic for input and AirPods for output only.

It stops when I lock the screen It is designed to continue in the background. If it stops, enable “Background App Refresh,” check Low Power Mode, and quit other audio apps that may interrupt it.

The Dynamic Island / Lock Screen display disappeared Live Activities have a maximum display time due to an OS limit (about 8 hours). Past that, the display stops updating, but HearRelay itself may keep running. Reopening the app refreshes the display. Note that even when the display stops, background audio capture may continue while monitoring is active. Use the app only for lawful, previously disclosed purposes, and do not place a device where it could capture the sound of people from whom you have not obtained legally required notice / consent.

Permissions checklist

Permission	Needed for	Settings path
Microphone	Monitoring in general	Settings → HearRelay → Microphone
Local Network	Pair modes (send/receive to other devices)	Settings → HearRelay → Local Network
iCloud (signed in)	Pair modes (discovering other devices)	Settings → [your name] → iCloud
Background App Refresh	Continued operation with the screen off	Settings → General → Background App Refresh

Even when Local Network or iCloud is unavailable, you can still use Standalone mode.

Privacy and security

• No data collection, no tracking, no analytics, no ad SDKs. The App Store privacy label is “Data Not Collected” across every category.
• Audio, recordings, and usage are never sent to a server. Processing completes entirely on the device / within the same local network.
• Pair discovery goes through iCloud Key-Value storage (your Apple Account space), and connections use the local network (Bonjour) only.
• Device trust can be revoked (Forget) later, and key rotation is supported.
• Benefits: audio cannot leak over the internet from a stolen or lent device, and the impact of an Apple Account compromise is limited to your existing set of paired devices.

Pricing and trial

• Try every feature free for 14 days (a feature gate inside the app, not a subscription — there is no auto-renewal).
• After the trial, a one-time in-app purchase (Non-Consumable, $4.99) unlocks it permanently. It is not an auto-renewing subscription.
• Family Sharing is supported, and you can Restore Purchases. Refunds are handled by Apple through Apple’s standard process (we never receive your billing information).

Important notice (safety and lawful use)

HearRelay is not a safety device, medical device, emergency-reporting device, security alarm, childcare-safety device, safety device for the elderly or those needing care, or life-support device. It is a general-consumer utility for supplementary monitoring and must not be your only means of supervision, watching over someone, anomaly detection, or emergency response (it assumes direct supervision and use alongside devices certified for the purpose).

Laws on recording and live monitoring vary by region, and may require the consent of everyone involved. Do not monitor / record conversations or private spaces unless you can confirm it is legally permitted. If the person recording is not a party to the conversation, stricter consent and legal requirements may apply. You are responsible for lawful use.

Frequently asked questions

Q. Can I use HearRelay over the internet? A. No. Both devices are intentionally required to be on the same Apple Account + same Wi-Fi. There is no internet relay, remote monitoring, or cloud path (a design decision to prevent misuse).

Q. Is my audio or data sent or collected? A. No. There is no data collection, tracking, or external transmission, and audio is never sent to a server. Processing completes entirely on the device / within the same local network, and audio between paired devices is end-to-end encrypted.

Q. Where are recordings stored? Can I export them? A. Recordings are stored on the device only and cannot be exported / shared. They are automatically deleted after 24 hours by default, and saving keeps them. They are never uploaded.

Q. Is HearRelay a subscription? A. No. It is a Non-Consumable one-time in-app purchase with no auto-renewal. After the 14-day free trial, a single purchase unlocks it permanently as long as you are signed in with the same Apple Account. Family Sharing is supported.

Q. Can I get a refund? A. Refund requests for App Store purchases go through Apple’s standard refund process (reportaproblem.apple.com). Refunds are handled by Apple under the App Store / Apple Media Services Terms, and we never receive credit-card numbers or other billing information. This statement does not limit any mandatory consumer-protection rights you have under applicable law.

Q. Why can’t I use it with the built-in speaker? A. When a mic and speaker run on the same device at once, feedback occurs, so the app refuses to start unless output is to headphones or similar.

Q. Can I rely on HearRelay as a baby monitor (safety device)? A. HearRelay is not a safety device, medical device, or emergency-reporting device. It is a general-consumer utility for supplementary monitoring. Do not use it as your only means of watching over someone.

Q. Which devices does it run on? A. iOS 18.0 or later / iPadOS 18.0 or later (up to the latest iOS). watchOS is not supported.

Requirements

• OS: iOS 18.0 or later / iPadOS 18.0 or later (up to the latest iOS). watchOS is not supported.
• Distribution: App Store (free download + optional in-app purchase)
• Languages: Japanese / English / French / Spanish / Brazilian Portuguese / Simplified Chinese

Support and contact

• Support (how-to, issues, purchases) — [email protected]
• Privacy Policy — how data is handled (no data collection / end-to-end encryption)
• Terms of Use — license, purchases, safe & lawful use, governing law
• Security & vulnerability reporting — where to report vulnerabilities

For privacy questions, write to [email protected]; to report a vulnerability, [email protected].