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2012- 01-03

Doorbot App

January 3, 2012

London Hackspace has an RFID card entry system that lets people register whatever RFID card they have in order to unlock the door (Since we're in London, most people are using Oyster cards).

Since I got a Galaxy Nexus I've been interested in playing about with it's NFC support, which is a layer on top of the usual RFID stuff.

I've written an Android App that uses your phone to grab the serial from an RFID card and then add it to your Hackspace account. So if you've got a phone that supports NFC you can add your own card your self.

apk here:


and code here:


to use it:

I was hoping to be able to generate a random serial number and get the phone to pretend to be a card and use that to activate Doorbot, but I haven't worked out how to yet. (The android SDK really focuses on NFC stuff, not the lower level RFID things, so it might be a bit like trying to spoof a mac address from http).

tags: hacks lhs android code nfc rfid


Aug. 8, 2013, 10:08 p.m. - John Coles

Hello, I have been investigating using my Google Nexus 4 to open my door. I currently have an RFID card and was wondering if I would be able to trouble you for a version of this that would just replicate the RFID card. It seems like it would be almost the same application just with out the auth on the LHS server. Thanks, John.

Oct. 29, 2013, 5:47 p.m. - Jasper Wallace

It will be much harder than a few line change to my code. AFAICT card emulation is possible with Nexus devices that have NFC/RFID, but the hardware is used to by the google wallet/payment services things and so isn't accessible by normal apps. It might be possible with Cyanogenmod or another non-google ROM.

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