BLE support in phones

What's a BLE?

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

Am 24.07.2026 um 18:20 schrieb john larkin: >> How ubiquitous is (or isn't!) this? Is there a general >> (temporal) cutoff point where its support is "expected" >> before which it is a rarity? >

I think Don is referring to:

Bluetooth Low Energy, basically low-speed low power wireless for small do-thats that run on batteries, like fitness trackers, heart rate monitors

any smart phone last ~12 years have it

The *API* has been in place. But, it's not a first class service like BT. You'd have to find and install an app to make use of it -- even if you were surrounded by BLE devices.

I don't think the user base is ready for this to the same extent they are BT earbuds, etc. Else, it would be prominently noted in the "factory installed" apps.

Imagine requiring a user to install an app to use his BT earbuds; how ubiquitous would they be, in that case (the bar to entry is too high)

best give up then

Exactly. Find a solution that is more mainstream. Less "customer support" involved.

From Android 4.3 (API 18) it is present.

Olaf

As I said elsewhere, support is present in the kernel. But, have any phones been shipped with an app that exposes it -- as "data", SMS, WiFi and BT are in most phones?

It is just part of Bluetooth. No need to do anything special at all. John

So, every IoT device (using BLE) near your phone is *visible* in the BT settings? I can dig up a 10 year old phone and see all of these??

What does "see" mean in your contect? I wrote BLE Apps than can work on old Android 4.3 and on new phones. Okay, on new mobiles there opens some windows and ask me to contact the programmer for a news version, but I can ignore it and it still works. And I also think a BLE device can try to hide, so is only visible for the app of the device. .-)

This gives you an overview:

Olaf

If you open the BT settings on a phone, the "nearby" (classic) BT devices are discovered. You can select one to pair with, etc.

Or not.

Just like you can see all of the available SSIDs when you open the WiFi settings.

No "special app".

Your app expects to talk to some BLE device, right>?

Remove the app from your phone. Can your phone "see" the device -- i.e., can it tell you that such a device is nearby?

As is classic BT. I (as the user) don't have to know that I'm looking for nearby BT devices that support A2DP in order for devices supporting it to be visible to my phone. Nor AVRCP, HFP, PBAP, HSP, etc.

I don't have to install a "special app" to *see* these devices.

And, I can "see" such devices using very old phones -- people are accustomed to seeing such things.

Can you see my BLE garage door opener? Or, do you first have to install "my app" that LOOKS for it?

what would be the point? if you don't have the app you can't use it

BLE keyboard/mouse and such recognized universal devices will show up

"What would be the point?> If you can't see the device, you don't need the app?"

if you don't have the device in front to of you you wouldn't know what to look for and you wouldn't need the app because you couldn't do anything with it anyway

You've got yourself trapped inside the box! <frown>

BLE isn't just "an invisible 30 ft cord" used to connect "you" to "some THING".

You can use them to indicate proximity to a specific location. Or, the availability of a particular service.

E.g., I could set a device in front of each bathroom in an airport, identifying itself as "BATHROOM" and you would know you were within

Or, a device advertising itself as "Text HOWDY for latest sale items"

And, you wouldn't have to power them from the mains OR replace batteries with any frequency.

no, but I know how it usually goes here. You ask a question and for every answer you get you invent a new reason why that's wrong

so if you want that you install an app for that

why anyone in their right mind want a phone to by default have something that notifies of every random BLE device you pass, and getting spammed with annoying ads on top of that ?

Because I've likely thought about these things more than any respondant. If I ennumerate all of the things that are wrong in my initial post, then you'll complain its too lengthy.

So, when you fly into JFK, you install the JFK app so it can tell you where you are on the concourse and how long the walk is to your gate or baggage claim or the nearest bathroom.

When you fly into Dulles, you install the Dulles app. Atlanta, the Atlanta app.

When you book a room at a Hilton, the Hilton app tells you where your room is, lets you interface to *your* HVAC, schedule a wakeup call, etc. Do the same for Marriott with the Marriott app. etc.

When you shop at Target, the Target app guides you around the store and highlights sale items. Costco, the Costco app. Walmart, the Walmart app.

etc.

And, you keep ALL of these updated so they are usable when you next might need them.

Or, you access the *up-to-date* web page for each of these WHILE you need said access and your phone is unburdened by them once you close the browser.

You obviously would have controls -- just like your phone doesn't notify you of every WiFi AP that you pass.

I don't know a whole lot about BLE but AFAIK it provides *communication* but doesn't define the *semantic meaning* in the way you want.

In other words your garage door opener has two messages, 'open' and 'close'. BLE lets you send message A or message B, but it doesn't define the meaning that says 'you send message A to open the door' and 'message B means close'. Without that, you can't construct a UI with buttons for open and close.

Zigbee, to use another example, does provide enough meaning that you can make those open and close buttons from a generic UI without needing to run code from the manufacturer. I don't think BLE does. You have make a device expect a HID profile (ie a keyboard) and maybe decide that 'Enter' means open and 'Delete' means close or something, but again you need manufacturer code to make that work (or somebody else has reverse engineered that).

There are various BLE profiles like fitness and audio where these things have been specified and they can be interpreted by generic code, but if you don't map to one of those profiles then generic support isn't possible.

What a stream of bits "means" can be interpreted any way you want. We tend to agree on what the bits that have been mapped to these characters mean. But, they could easily be interpreted to mean ANYTHING else.

I can set my SSID to "Dr Alonzo's Cardiology" and convey (deceptive) information to passersby looking at available BT connections.

That's up to whomever defines that interface. A and B might, instead, be "turn on the light that is part of the opener mechanism" and "prevent any other WIRED controls from being recognized by the opener".

The FIRST issue to address is how ubiquitous the underlying technology is and how familiar it is to users: "How ubiquitous is (or isn't!) this? Is there a general (temporal) cutoff point where its support is "expected" before which it is a rarity?" The *hardware* and OS support has been around. But, it hides behind specific applications tied to specific peripherals -- a small subset of how it CAN be used.

Folks think of Bluetooth (Classic) and WiFi as "connectors". You "plug in" your earbuds and "plug your phone" into the internet. *YOU* control that action, for the most part. Unless you wander too far from your phone (or the AP), you EXPECT the connection to persist (barring hardware failures)

They don't think of it as something that they can have fleeting interactions with and still extract value. Waiting for a table at a restaurant and "seeing" YOUR expected wait time updated dynamically (you will NEVER connect to that instance again yet it has value NOW). Or, navigating a hospital or other semi-public facility for the first (only?) time. Or, standing in an endless line at Disney{Land,World} and receiving an updating notification "Wait time from this point is 45 minutes" -- which obviously changes the nearer you get to the destination.

It's only when people become accustomed to such interactions that they start *looking* for them. Otherwise, the technology has no value to them.

Appliances now have the ability to alert their users of significant events. But, do so using heavy protocols that often rely on (external) third parties (why can't my washing machine contact me directly without having to go through a manufacturer's server?)

If you can't *see* that BLE devices are present, then you don't consider looking to use them.

If I walk into a coffee shop, store, doctor's office, etc. there is no guarantee that they will DISPLAY an access point that I can use, there (as a courtesy). If my phone couldn't show me the SSIDs that it was encountering while there, I likely wouldn't notice the one named "Joe's Coffee Shop" so would not avail myself of that capability.

One wouldn't know the airport had beacons strewn about at known locations to assist with pedestrian navigation unless you could *see* those. Seeing them once might encourage you to investigate what sort of apps can exploit them and how to acquire those.

As I said upthread, you definitely wouldn't want to be bothered with installing an *app* to take advantage of these as their use frequency would likely approach zero. But, (as also indicated) referencing them in a web page that a facility can serve via a URl broadcast by a beacon (cf Eddystone) makes a lot of sense -- IF you are savvy enough to look for them.

From the informal survey I've done, most phones don't NATIVELY report the existence of proximate BLE devices. One has to install a scanner if you want to see what's available. And, tolerate the battery drain if one wanted to *follow* the signals available as one wanders about.

And, Average Joe's likely would just find this information confusing. They aren't sophisticated enough -- YET -- to see its value. If they've opted to buy a fitness tracker or watch, then their knowledge of BLE is hidden inside that product offering; they know nothing of what *else* it can do for them.

Nothing forces you to use a technology in a particular manner.