Android Apps that measure breathing?

[Blazing Black Beard]

Whilst Sleep as Android is a very useful piece of Android software to visualise the quality of sleep one gets during the night, along with SPo2 monitoring via Bluetooth, without the oxygen monitoring Sleep As Android is only partly useful (it was in my case for sleep apnoea). The software is severely limited to only really allowing you to effectively use a small subset of it's vast features without a Bluetooth SPo2 monitor. You'll just get reliable snoring detection and satisfactory to good sleep stage detection without the oxygen monitoring. This is not useful if you're needing breathing detection and monitoring.

Also there is no substitute for properly physically measuring the diaphragm. Sonar and the accelerometer/gyroscope do not work properly, especially if there is someone in bed with you. Also sonar and snore detection can easily be interfered with and report wildly inaccurate results if you have an open window and things like traffic outside or other loud noises whilst you sleep. It's better to use these whilst in bed alone, with double glazing windows closed and zero external noise, but this will not give anywhere near what you are looking for if you want to know how you are breathing at night.

An external device with more suitable sensors is always needed so you are always going to have to use something else as a stand alone option. You can use other devices in tandem with software that runs on general purpose computing devices including phones and tablets and there are some Bluetooth devices available that provide some useful monitoring functions, but again, these will not provide you with diaphragm and breathing detection, only SPo2 levels and pulse rate. 

Nothing is available as an app because phones simply lack the sensors or inputs to enable them to record any of this data in any meaningful, repeatable and reliable way. Even the SPo2 sensors near the camera modules on phones can't be used reliably and it's unsafe to do so, as is using the phone as a movement sensor, having it strapped to your diaphragm. Who want's to be strapped to a hot charging device all night?  I certainly wouldn't take that chance and the device probably wouldn't last all night anyway when it's constantly active using the SPo2 sensor and monitoring accelerometer/gyroscope.  Even Sleep As Android requires that the device be on charge whilst sleep monitoring with Sonar or the accelerometer/gyroscope s they say it uses lots of energy and will probably switch off before waking due to low battery. 

The only way to do this would be to use something like the match box sized Resmed T3, which is tiny and extremely easy to sleep with. It will suit your needs perfectly to monitor your sleep breathing patterns.  It uses a chest strap to measure your diaphragm for physical expansion whilst breathing, a finger probe for SPo2 readings and breathing detection via thin nostrils tubes hooked over the ears. This is the only way you are going to get what you need as there are no phone apps that allow the direct measuring of diaphragm expansion and breath rate.

You may find one to purchase online if you look hard enough. Quality used units are being sold all the time.

   

[sheepless]

Blazing Black Beard, I don't disagree with your overall point that phones aren't up to monitoring breath by breath but I do have a small difference of understanding on one point:

"Even Sleep As Android requires that the device be on charge whilst sleep monitoring with Sonar or the accelerometer/gyroscope s they say it uses lots of energy and will probably switch off before waking due to low battery."

I do not believe this statement is true, or at least it wasn't a year or two ago when I was using sleep as android. I don't remember exactly but don't think I ever used more than about 10% or 20% of my galaxy note5 battery overnight with sleep as android running. (on an unrelated note: snore recordings take up a lot of storage space though.)

as I recall the app developers caution it might be necessary to keep older phones with earlier android versions and maybe cheaper phones with smaller batteries plugged in if the battery doesn't last the night. but it was certainly not a requirement when I was using it.

[Blazing Black Beard]

The battery charging warning always appears when using sleep tracking on Sleep As Android and appears every time to warn that the battery charger should be connected. Dismissing this warning doesn't stop it from reappearing every single time that sleep tracking is activated. On the Samsung Galaxy S7 Edge and Samsung Galaxy S9 plus, the battery does drain very quickly whilst using sleep tracking, hence the reason I have always connected the charger.

[sheepless]

yes, I see what you're referring to. when you first start sleep tracking there's a list of generic instructions and warnings including things like 'lie down and place the phone on the mattress...', 'verizon backup assistant may be incompatible' and 'better charge your phone to prevent discharge before alarm'.

no requirement to charge and not necessary in my experience. obviously, however, phone capabilities vary.

[Blazing Black Beard]

I didn't say it was required by the developers of Sleep As Android, but it is suggested in a warning every time the software sleep tracking is activated. In my case and many others, in relation to the S7 Edge and S9 Plus, it is a good idea to, as the battery will most likely drain, especially when these batteries don't last half as long after about 14 months of ownership. So from personal experience, I'm stating that charging whilst using software such as this is definitely required.

I've had my S9 Plus now for 18 months and I'm not going to get a new phone any time soon, but the battery life is now approaching unacceptable, so each day I contemplate taking an extra battery with me wherever I go. This means that leaving the phone charging whilst apps like these run is essential.

Strapping an extra battery to your body so your phone does not die mid-recording is not a realistic option (and would prove very awkward and uncomfortable, in addition to the awkward and uncomfortable large computing device already strapped to your body), so Sleep As Android (and other mobile device sensor exploiting Android software), whilst having it's uses, is far from ideal and there are much better options that don't require rigging together a DIY system that sort of works, but, at best, works in a mediocre fashion, is uncomfortable, impractical and awkward to use, and doesn't produce the quality recording and proper data that you really need, i.e. diaphragm expansion regularity and breath detection. No general purpose computing device can produce any meaningful data as a stand-alone option. 


Besides, most people won't want a phone or mobile device in continuous contact with their body to gain slightly more accurate accelerometer or gyroscope monitoring, which won't give a true indication of diaphragm expansion anyway, as it can't possibly be accurate enough to measure the minute movement differences involved in detecting a normal breath movement and be able to differentiate between that and an obstructive apnoea, where the diaphragm will still move due to muscle contraction but no air would be entering the lungs.

Sonar systems might be a little more accurate than accelerometer and gyroscopes (this is why Sleep as Android has this option and in any case, they suggest putting the phone close-by, not on your body), but then these are also prone to false readings and generally suffer a massive amount of inaccuracy due to environmental conditions, such as proximity variations, external noises and believe it or not, sound absorbing furniture, fixtures and fittings in and around the sleeping area. Sonar is a volumetric occlusion based sound reflective sensing technology, and having anything in the immediate environment that alters the way sound is reflected and propagates greatly affects the quality of the results. Sonar is nearly useless in my envoronment as there's way too much sound absorption and interference happening, not to mention moving objects like occilating fans and air conditioners, and things like open doors close by, changing the sonic environment as they flap about in the breeze.

Devices like the Resmed Nox T3 are nowhere near the footprint of a phone or other mobile device and can comfortably be worn on a body strap as they are designed to be comfortable to wear. They are not prone to any of the external environmental influences either, apart from the sound recording part which detects snoring. They incorporate positional sensors in the device that record every movement, including sensing whether you're on your back, front or one of your sides, and straps that accurately measure diaphragm expansion that easily differentiate between a regular breathing expansion and a muscle contraction during an obstructive apnoea.

They also have the singular most important sensor that you require (that doesn't appear on any general purpose computing device or in any commercially available wearable Bluetooth sensor), which is a physical breath detection system based on tubes and real air pressure/movement, which can accurately record whether air is entering your lungs or not, as opposed to a crude gyroscope/accelerometer implementation that can't possibly detect air entering your lungs.