Guide / Updated 24 October 2026
Sound machine or iPhone app?
A separate sound machine keeps the phone free and may have dedicated physical controls. An iPhone app is easier to carry and can save mixes and timers. Source ↗
- A separate machine has physical controls and its own speaker.
- An iPhone app travels easily and can save mixes.
- Both need a quiet-first room setup.
How to try it
Choose based on where you sleep and how you control sound when tired. Check whether a machine’s buttons and speaker placement suit your room; check whether an app continues playing on your phone when the screen locks.
- Choose based on where you sleep and how you control sound when tired.
- Check whether a machine’s buttons and speaker placement suit your room; check whether an app continues playing on your phone when the screen locks..
- Neither format tells you the loudness at the pillow by itself.
What to consider
Neither format tells you the loudness at the pillow by itself. Set up either one at a low level and recheck after moving it.
Separate hardware from features
A sound machine can sit in one stable place and offer a tactile button when you are tired. It also occupies an outlet or needs batteries. An iPhone app is portable, can remember a mix and use the phone’s existing screen and speaker. The feature list alone does not tell you which device will be more comfortable in your bedroom.
Ask who will operate it at night. Someone who dislikes unlocking a phone may value a physical knob; someone who travels may prefer a saved app preset.
Compare the real speaker
A separate machine may have a fuller speaker than a phone, but models differ. A phone can connect to a Bluetooth speaker, changing its output again. Put whichever device you choose in its final location and start at a low setting. The slider or knob does not measure the level at the bed.
A larger speaker can make bass-heavy brown noise much more prominent, while a tiny unit may sound hissy. Listen to the actual hardware, not only its advertised sound names.
Consider reliability and routines
A machine is independent of calls and notifications, while an iPhone app can use a dedicated audio session and saved controls. Either can fail with power loss or an accidental setting change. Test timers and alarms before relying on them.
SleepMix includes a sleep timer, saved presets and optional Pro wake controls. A basic machine may offer fewer controls but be simpler for a guest or caregiver to operate.
Child placement is format-neutral
The AAP advises sound-machine users to keep the device as far from an infant as possible, use the lowest volume and limit duration. An app on a phone does not change that guidance. Keep cords and devices outside the cot.
Choose a setup another caregiver can reproduce consistently without moving a speaker closer or raising it to overpower a noisy room.
Spend only after testing your need
The free browser generator can show whether a steady noise color helps at all. If you need a portable saved mix, try the free SleepMix app and inspect its purchase terms before buying Pro. If tactile controls are crucial, compare physical machines in person when possible.
A “best” choice depends on the room, device and nightly habits. Start with the smallest solution that meets the actual problem.
Common questions
Will a dedicated machine work without a phone?
Typically yes, but check the exact model’s controls and power needs before buying.
Does an app need a subscription?
SleepMix is free to download with optional in-app purchases; current terms appear in the App Store and app.
Which option is safer for a nursery?
The AAP advice on distant placement, low level and limited duration applies to sound machines regardless of format.