An old Android phone works as a two-way audio intercom: you listen to the room through its microphone and talk back through its speaker, from a browser anywhere. In AndrIoT you hold the talk button in the live view, and you can also use text-to-speech or play a siren instead of speaking.
This article covers setup, the best uses (nursery, workshop, front door, elderly relative), how to avoid echo and feedback, and the privacy points to think about before you put a listening device in someone's home.
Key takeaways
- Listening uses the phone microphone, talking uses the phone speaker. Both go through the live view.
- Text-to-speech says typed phrases. A siren and sound playback are also available.
- Echo happens when your own speaker is near your microphone. Use headphones and keep the volume moderate.
- Phone speakers are small. Expect clear speech at close range and a thin sound at distance.
- Always tell people when audio is being listened to.
What two-way audio can do
Two-way audio means a live voice link between your browser and the phone. It is not a phone call: no number, no ringing. You open the live view, listen, and talk when you want to.
| Feature | What it does | Good for |
|---|---|---|
| Listen | Streams sound from the phone microphone | Checking on a room, hearing a visitor |
| Talk | Plays your voice through the phone speaker | Calling a child or pet, speaking to a courier |
| Text-to-speech | The phone speaks a typed phrase | Consistent messages, noisy places |
| Play sound | Plays an audio clip | Chime, reminder, alert tone |
| Siren | A loud alarm tone | Deterring an intruder |
| Scheduler | Does any of the above at set times | Daily reminders. See schedulers |
Setup
- Install and pair the app as in the setup guide.
- Allow the microphone when the wizard asks. Without it the phone cannot send sound.
- Raise the phone media volume to about 70% so speech is audible. Do it on the phone.
- Open the live view and press the audio control to listen.
- Hold the talk button and speak. Release to listen again.
- Test text-to-speech by typing a phrase and playing it.
Fixing echo and feedback
Echo is the main annoyance. It happens when your voice comes out of the phone speaker and goes straight back into the phone microphone, or when your own laptop speakers feed your microphone.
- Use headphones on your side. This fixes most echo.
- Lower the phone speaker volume a little, to about 60 to 70%.
- Place the phone so the speaker is not facing a hard wall.
- Use push to talk, not an open channel.
- If the phone has a hardware noise suppression setting, leave it on.
Practical uses
Nursery or sibling room
Say a soft word through the speaker, or use a calm pre-typed phrase. See the baby monitor guide.
Front door
Speak to a courier without opening the door, or make it sound like someone is home. See the door camera guide.
Workshop or garage
Call someone from the house without walking out. A loud siren works as a call bell.
Elderly relative
A phone that is always on, plugged in and sitting on a shelf is an easy way to check in, with their agreement. Agree that it is there and when you will use it.
Pets
Some pets respond to your voice. Others get anxious. See the pet camera guide.
What to expect from a phone speaker
Phone speakers are small and sound thin. In a quiet room it is fine. In a noisy workshop, text-to-speech at full volume works better than a whispered voice. The microphone picks up near sounds well and distant sounds poorly. Wind noise and a case over the microphone hole both reduce quality.
Audio needs a good connection. If the picture freezes, the voice will break up too. Lower the video quality or move the phone closer to the router.
Privacy and consent
Listening to a room is more sensitive than watching it. In many places, recording or listening to conversations without consent is illegal. Tell people when a microphone is active, avoid bedrooms and bathrooms used by others, and never use it to listen to people who do not know. See the legal and privacy notes. Live audio goes directly from the phone to your browser and is not stored unless you turn recording on.
Getting clear sound
Sound quality depends on three things: the phone microphone, the room and the connection. A few small changes help a lot.
- Clean the microphone hole. Dust and lint at the bottom edge of many phones muffle sound. A soft brush or a dry toothpick works.
- Take off thick cases. They can cover the microphone or speaker opening.
- Avoid hard, empty rooms. Bare walls bounce sound and make speech boomy. A rug or a curtain helps.
- Keep the phone off a vibrating surface. A washing machine or a fridge adds a constant hum.
- Use Wi-Fi close to the router. If the connection stutters, audio breaks up first.
| Problem | Likely cause | Fix |
|---|---|---|
| Voice is faint | Phone volume low, or case covers speaker | Raise media volume; remove case |
| Voice is distorted | Volume too high for the small speaker | Lower to about 70% |
| Room sound is hissy | Far from the source or noisy room | Move the phone closer |
| Echo when talking | Your speakers feed your microphone | Use headphones |
| Audio drops out | Weak Wi-Fi | Move closer to the router or lower video quality |
Siren and sounds
Besides voice, the phone can play a siren and audio clips. A siren is useful as a deterrent when the alarm is armed and someone moves the phone, or when you see a visitor on camera who should not be there. Test it once at a polite hour and warn the household, because it is loud. Keep a note of the volume you used so you know how it will sound in a real event.
When voice is not the best tool
Two-way audio is useful, but sometimes another feature does the job better.
| Situation | Better option | Why |
|---|---|---|
| A noisy workshop | Text-to-speech or siren | A typed phrase at full volume cuts through noise |
| A repeated daily message | Scheduler | No need to be there |
| A sleeping baby | Quiet text-to-speech or nothing | A voice can wake them |
| A real emergency | Phone call or emergency services | The intercom is not an emergency line |
| A person who cannot hear well | Screen message | Show text on the phone screen instead |
The screen display feature can show a message on the phone for someone who prefers text. See the digital sign guide.
Pros and limits
Pros
- Talk and listen from any browser.
- Text-to-speech, sounds and siren in the same tool.
- No phone number or call to set up.
- Works with schedules for reminders.
Limits
- Small speaker and microphone limit quality.
- Echo needs headphones or lower volume.
- Needs Wi-Fi and power.
- Legal and privacy duties apply to listening.
FAQ
Can I talk through an old phone from my browser?
Yes. Open the live view and hold the talk button. Your voice plays through the phone speaker.
Can the phone read text aloud?
Yes. Text-to-speech says a typed phrase through the phone speaker.
Why do I hear an echo?
Your voice is coming back through your own speakers into the microphone. Use headphones and lower the phone volume.
Is it a phone call?
No. It is a live audio link in the dashboard. There is no number and no ringing.
Is it legal to listen to a room?
It depends on where you live and who is in the room. Get consent and avoid private spaces. Check local law.