Solution: Bluetooth Separation Alert as Perimeter Alarm

By: Frank Engelman.  Updated: October 26, 2020.


The Problem: Dementia Patient Wanders (Living at Home)

Your loved one tends to wander out of the yard when you aren’t looking. She has dementia, and you worry she will get lost. 

Although you could get an elderly GPS tracker, they may refuse to wear it, and cell coverage in your area might not be reliable..... More about the Problem


Solution: Bluetooth Separation Alert as Perimeter Alarm

My first thought was to use those tiny Bluetooth tracker tags that are for finding car keys, as they have a feature that will alert your phone if you leave something behind.

Unfortunately, the major tag manufacturers are NOT supporting detecting if the tag moved, but the phone stays stationary. I thought that would be an excellent Use Case for getting an alert if someone took your laptop bag at a coffee shop, but the manufacturers have no interest. One even said they excluded that by design as a benefit!

After testing MANY Bluetooth tracker devices, we finally found one that, if attached to your wandering loved one, will sound a repeating alert on a smartphone. This particular device is tiny (1.4” * 2.4”) and very thin (0.11”) and, if attached to a clip, can be discreetly placed on your non-compliant loved one.


See the Solution in Action in this Video




After I tested the “separation” alert feature on several Bluetooth tags, I found that they alert you only if you left the tag behind. They did NOT provide a separation alert if the phone stayed stationary, and the tag moved away!


Not all Bluetooth Tags Worked For This Use Case

I found that MANY tags did NOT provide the separation alert that I needed when just the tag moved.

These tags did not work for this specific "use case", although I have found several of them to work well for other situations.

  • Tile
  • Chipolo
  • TrackR
  • CUBE
  • Pebblebee
  • Cubitag


These Tags Allowed My Idea to "Work"

However, The following two tags did give an alert when the tag moved away from the phone:

  • Rinex
  • Wopin (GoFinder app)

See these tags and the clip we used on Amazon at Rinex and Wopin and the clip we used.   [affiliate links]




My son mounted the Wopin Bluetooth tag inside a Fitbit clip, and it's ready for testing.


Bluetooth tracker tag

Caption: Bluetooth tag and clip "ready to go".



Initial Results

In our testing here around the home, we found that it set off a separation alert on a phone if we moved the tag about 50 feet away from the phone.

We have not yet had a chance to evaluate how well this works in a "real world" situation with a person with dementia.


Want To Hear When We Finish This Evaluation?

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Learn More

For more information, you can learn about my personal experience solving Alzheimer's wandering, and read an overview of a broad range of solutions at "Location Devices and Trackers for Dementia".




More Like This

This is part of a series of "Problems" and DIY Technology "Solutions" to the challenges faced by older adults, by Frank Engelman. 



Discuss this solution


from Kevin Risley (unverified) at July 19, 2021

I have an idea I would like to discuss. The slight spin is that I am interested in protecting infant/young children. If you would be able to answer some question to help me, it would be appreciated. Thank you. Kevin Risley


from faengelm (member) at July 20, 2021

I'd be happy to answer your questions. Just post them here.


from DavidD (unverified) at September 18, 2021

50 feet away is to far for what I want to use this tracker with. I wanted to know if its possible to adjust the distance to lets say 15 feet. I plan on attaching one to my wallet and alert my phone if its 15 feet or more away.


from faengelm (member) at November 01, 2021

Hi David,

I checked into several of these tags, including the new Apple AirTag. With IOS 15, it does offer a separation alert and a "range adjustment", but its minimum is greater than 50 feet.

I then did a test with the GoFinder tag I recommended in its article, and by wrapping it with aluminum foil, I can reduce its range to about 10 feet. What is neat about this tag is that its very slim and would fit in a wallet.

What is a bonus for the “wandering wallet” application you mentioned, is that the tag will also alert you if the phone starts to wander away!

When at home, you can also turn off the separation alerts manually in the app, or automatically when it detects you are in the range of your Wi-Fi


from DaveT (unverified) at November 05, 2021

Hi frank. This is another david and I just came across your reply. I really like this idea of wrapping the tracker in foil to reduce the separation distance. I had not even considered it. It’s a really simple but effective idea.
Quick q - do you find the tracker reliable enough? . I find that some trackers just disconnect as you go in and out of the home and then don’t reconnect when you really need them. What’s been your experience of this tracker over time, or is it too early to say.


from faengelm (member) at November 05, 2021

Hi David,

I haven't tested this tracker over a long enough period to rate its reliability outside of the home.

The elders I deal with are mainly interested in finding items within the home

I would be interested to know which trackers you have found to be unreliable.


from Robert Millican (member) at January 17, 2022

Wrapping the device in aluminum foil is an interesting idea... never thought of that.  I am fascinated by the ability to track items via trackers using their own network or Apple's "Find My" app.  I am not sure I would trust any of them to giving me a separation alert if it was attached to a child.  I have tested numerous separation alert devices and have limited their application to personal items only. Even though trackers are getting some bad press due to stalkers and vehicle thieves, they do serve a very good purpose. One can only hope that Apple figures out the security issues soon. But, even with these tracking capabilities, they are dependent on not losing the phone. Recently, a new generation of phone reminder devices (PRDs with no app required / no-tracking) are now being sold that work complimentary with the Apple products and the typical tracker, reminding you that you have left your phone behind. (After all, you need your phone to operate the tracking app.) The PRDs are short range adjustable alert distance reminders (not finders) that are extremely reliable. After a few months, I have found them (mine is the Prox PRD) to work very well (zero false alerts) and compliment the AirTags capabilities. I am looking forward to the future of all this great new technology.


from faengelm (member) at January 18, 2022

Hello Robert,

Thanks for the tip on the Prox PRD.

The only ones I have seen require an app running on the phone.


from Robert Millican (member) at January 19, 2022

Hi Faengelm,

Yes, every proximity device I have ever tried has had an app.  The problem is you have to keep the app open and if the phone shuts down the app, you get an alert.  Or, if the app is not open you don't get an alert. These other app-based devices tend to have a lot of false alerts.  They want solve some of these issues with alert free zones and alert free times, but that can create other issues of no alerts when you need them.  Because the Prox PRD has an accelerometer, it only alerts when on the move so you don't get any false alerts in the middle of the night and it handles OS updates, "airplane mode", and turning off Bluetooth seamlessly.  I also read that the Prox PRD is the only device that alerts you even when the phone is turned off or the phone's battery is dead.  Pretty neat stuff.

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Target customers & users: 
Family of the aging
How important is it?: 
Big problem
Key words: