Gredelin for Android published

Today I published a new app for Android called Gredelin. It is a little toy that works with the NFC reader on my Nexus S.

While experimenting last week, I discovered that the NFC reader detects the presence of the London Oyster card, which we use to pay for public transport here. It also works with the Access card used in Stockholm, which apparently uses the same technology. This is pretty cool, because lots of people have one of these cards! (Of course, not many people have an Android device that can read NFC yet, but hopefully that will change.)

Now, it would be cool if we could read some interesting data from the travel card, such as how much money is on it, but sadly I don’t think this is possible because the cards are encrypted. What we can read however, is the numerical ID of the card, which is sufficient to do some neat things. Since we can tell which card is which, we can assign activities to cards!

So I created Gredelin as a bridge to connect that ID with an activity. Gredelin stores IDs for any card you show it, and lets you assign an activity to launch when you show it the same card. Presently it can launch apps and open web pages. So for example, you can set it to open the Transport for London web page when you show it the Oyster card, which is pretty neat.

So if you have a Nexus S, visit the Android market and install Gredelin!