At my workplace we use HID ProxCard II cards to enter the building and to open individual doors. Everybody has a card with their picture printed on it. The problem is that I keep forgetting mine, plus I’ve had it for such a long time that the card started to disintegrate and it looks rather nasty.

I really wanted to just use my Android phone in lieu of the card, but it seems like HID cards are not compatible with NFC 🙁 This of course wasn’t going to stop me. Somehow I wanted to “fuse” the card with my phone. If my phone had a plastic case or cover, I could just slip the card inside of it. But I own an HTC Once and since it’s made out of aluminium and gorilla glass, I don’t really need (or want) a cover for it. I decided to use a sticker to attach the card instead. I ordered a custom-fit sticker from SkinIt with a cute picture of my boys on it. Now I could finally start my project 🙂

First I cut off a small strip of plastic along every edge of the card, starting with the top. Then I removed the front layer with the printed picture. It was clear that there were two additional layers to the card. Finally, I carefully separated the two remaining layers, exposing a copper coil and something that looked like a microchip.

Next step was to affix the layer with coil to the back of my HTC One. I chose not to remove the coil from the plastic it was glued to, and instead to attach the whole thing to the back of the phone with scotch tape. Of course I rounded it off a little bit witch scissors, just to make it look better.

The final step was to place the SkinIt sticker over the back of the phone. Sadly that didn’t go as smooth as I hoped. Since the coil and microchip are not perfectly flat, you can see a small bulge. It will take some time to get used to it, but ultimately it should not be a big deal. A small price to pay for the convinience. Here is a photo of the finished product. Now I just need to remember to carry my phone around with me at all times at work 😀