Long walk / forced high heels training with NFC tags

[sunflower]

Hi, I found several ideas on how to enforce a long walk / high heels training using rather complicated setups.

I just had the idea to use NFC tags instead. You just mark two (or more) places in your house with these tags. Each tag holds different data like just A or B. You lock your high heels and now you have to visit on tag after the other, maybe multiple times. An app keeps track of your progress. When you finally finished walking, the app will give you access to the keys, for example similar to the time lock for images app or something.

I guess it would not be too difficult to write an android app which you can configure with the number of tags, the number of iterations and the release info (the image) - and once started you have to walk.

I can think of more configurations options, like a time limit to walk from one tag to the other. if you don't make it within the time, you have to start over or another iteration is added.
If you have more than two tags, there could be a random mode and you don't know which tag you have to walk to next.

Of course you can also put those tags outside, even in public places. I can imagine a lots of possibilities - and it is easy to vary.

Now my question: does anyone know if such an app already exists? Or maybe there is a better idea?

(of course you need a backup mechanism, but with the app installed on your phone you don't need internet connectivity)

Thanks
Sunflower

[Kinbaku]

Welcome sunflower to BoundAnna.
I remember that we discussed something like this on BoundAnna.
Like this fictional story.
If you can program, contact Shannon via PM.

[Shannon SteelSlave]

Aloha from Bound Anna, Sunflower

[eki]

This is an idea I've been toying with as well! I was originally inspired by a story on literotica. Right now I'm considering an integration with my existing lockbox where you can script your phone to only unlock the box/ give the password to the box when certain criteria have been met like GPS position or scanned bar/QR code. Of course right now it's also possible to go low-tech and drop a note with (part of) the password somewhere to be retrieved. So if I were to develop that companion app, I'd want it to have novel features. But I think the toughest part is securing the system against cheating. Requiring the phone to move to a certain location is easy of course but requiring the person to be in a location for a certain time or for them to not be in a location is very hard to properly verify. Maybe with a BLE tag embedded in a locked collar or something similar.

[ruru67]

Lessee .... parts: a lock box with a combination; a small Arduino board, with a battery, NFC (or RFID) reader, and some kind indicator as to whether an RFID card read correctly (e.g. red/green LEDs and/or a piezo buzzer), and if so, whether it was in the right order or not; and a stack of NFC/RFID cards.

The Arduino program does four things:
1. Allow you to program the lock box key into the Arduino.
2. Read the NFC/RFID tags one by one, store in memory.
3. Read the codes back in order. If read out of order, indicate so.
4. Allow access to the code.

Steps 1, 2 & 4 can be done with the device attached to the computer.

The idea is that you (step 1) first put in the lock box combo - you'll need one with a long combination that you can't easily memorise. Lock the box, program the combo into the device, and discard the combo. Then (step 2) take a bunch of tags, read them in, shuffle them, and distribute them around your house, property, neighbourhood, region ... however far you want to go ... You might want to attach them to things so they can't be rounded up and tried at leisure.

Lock yourself into the outfit / bondage you want (you did put the keys in the lock box, right?), and now you have to visit every location in order. When you have, and only when you have, you can plug the device back into your computer and retrieve the combination.

Variations include putting time limits on things, or delays so you have to wait before attempts. You can make the trip longer by demanding a full restart when you enter the wrong RFID card, so you have to go back to the first one again, then to all the one you know so far before trying the next unknown.

And because I love electro zappy things, instead of LEDs or a buzzer, I'd use a 433 MHz transmitter to talk to a shock collar as my indicator... (I have code to drive these...)

[eki]

Is it really worth it to go with a microcontroller for this? Sideloading an APK is so much more accessible than writing firmware, sourcing hardware and making an enclosure for MCU + battery + NFC breakout. I have my RF shock collar listening using an MQTT bridge so that's easy to integrate into a phone app as well.

Alternatively, it is not impossible to use a webapp. I'm not sure if there's an API for NFC but QR via webcam should be easy. Solves the hardware constraints & is not locked to Android or iOS. Just have to come up with a reasonably cheat-proof way of keeping the password out reach for more tech-savvy users. (but a large QR code that is validated in a backend can take care of that I think)

[ruru67]

Is it really worth it to go with a microcontroller for this?

Two reasons: 1. cheap parts; 2. fun project.

I'd probably want to have a more direct and automated link between the device and the lock box - but then I already have a fully programmable lock box...

[sunflower]

Thanks everyone. Indeed, instead of writing a phone app, a webapp would most likely do it as well. I haven't done it, but I think you can store a URL in the NFC tag and then trigger the webapp from there. Old fashioned QR codes would do it as well
As I've never written a phone app before, I might first try the webapp approach.

[ruru67]

The QR code approach does mean you don't need any special code on the phone or any extra hardware - just generate QRs with URLs with opaque codes on them and distribute them around, then when you do your walk, submit them to your webapp just by scanning them, and the webapp can decide if they're correct, in the right order et c. The on;y thing the webapp would need is some way to open your lock box when you have satisfied it.

[sunflower]

I gave this another thought. I think you need an app an the phone. There are two reasons:
1. Without an app, you need a user navigating the phone. If a QR code is scanned / a tag found, the user needs to confirm the URL so it gets opened in the browser. With an app this can be done behind the scenes by just bringing the phone close to the tag or the camera close to the QR code. no fingers needed
2. If the control is via URLs called from a browser, the user can easily fake getting to the required place by typing in the URL or once a place is visited reloading the URL in the browser
This also means that NFC tags are a better choice over QR codes

[eki]

QR codes don't need to open URLs. They can contain just a value. What I envisioned was a webapp that is loaded from the browser, and the webapp uses the camera and ingests the code. No special interaction required from the user, just have to open/keep the browser open. The scanned code can be sent via POST to the backend so the user isn't presented with the value. Not airtight but most users won't have an attack proxy set up on their phone.
NFC tags can improve on security here, but only marginally and that would require specific tags and for the server to handle the keys for them.

Using a native app still definitely has benefits. Offline use and NFC scanning without waking the screen (i think) included. But if I were to develop a solution (and I'm really really tempted) I'd feel those benefits don't outweigh the increased development cost and/or exclusion of iOS users

[Kinbaku]

My magician friend uses QR codes so that when a spectator read them, he is directed to a special website he created. For example, movies for each card of a deck.
In the same way, you can distribute different QR codes that will take you to the next QR code when you see the image or movie set with that next QR code that you need to read.

For example, if you randomly distribute 10 QR codes, you must go through them all in order before you receive the code on your mobile phone from the liberating key.

[ruru67]

I gave this another thought. I think you need an app an the phone. There are two reasons:
1. Without an app, you need a user navigating the phone. If a QR code is scanned / a tag found, the user needs to confirm the URL so it gets opened in the browser. With an app this can be done behind the scenes by just bringing the phone close to the tag or the camera close to the QR code. no fingers needed

This is true. Your bondage would require you to be able to drive your phone. That might be fine for a "dressed" long walk, or a scene one where you're bound awkwardly and with limited mobility. But if you can't unlock your phone, operate the touch screen, or see well enough to aim the camera and confirm the QR URL, it's not going to work.

2. If the control is via URLs called from a browser, the user can easily fake getting to the required place by typing in the URL or once a place is visited reloading the URL in the browser

I don't think that's true if you design your webapp well enough. Your QR codes would contain random opaque strings - long enough that you can't remember them even if you see them - that only the webapp knows. You'd generate them, print QRs for your "rendezvous cards", each QR card containing the URL to submit one of the strings to the webapp, feed the list of strings to your webapp, and then remove them from any accessible storage. You'd obviously have to deny yourself "back door" access to those codes somehow, or at least make it more trouble than it's worth to "pick the locks", so to speak. It'll depend on what you're running your webapp on of course, but if your phone doesn't have access to the app code, and you've locked yourself out from access to any devices that do, then it's as secure as you need.

[DedLoveYou]

Android App developer here! I would be happy to help.
Do you want to scan multiple NFC tags, save them and the app locks away the code until you scanned all?

[sissystephanie81]

Can't help with development, but very interesting in seeing something like this come to phone or web app.