Reading information from Magnetic stripe using objective C

I couldn't find any general API or helpful article for reading data from credit / debit card.

There is none. It's a coupled hardware/software solution.

There are vendors who sell credit card reader hardware devices for iOS, and provide an SDK so you can integrate credit card processing into your own app. Here is one example.

http://www.idtechproducts.com/products/mobile-readers/112.html

Some SDK's include the capability to transact with merchant banks.

I am confused... How will you read the credit card without purchasing a credit card reader device? Just use the SDK that comes with the device you purchase. If you want to make sure the SDK is robust before purchasing a device, then ask the company in advance for documentation.

If you can get by without scanning the magnetic stripe, there are SDK's that use the camera to take a picture of the credit card and use OCR to get the number.

https://www.card.io/how-it-works/

Somewhat related to this, I need to do the same thing, but not to read a Credit/Debit card mag stripe, but a mag stripe from a tradeshow badge.

Any ideas?

Thanks in advance!

Did you read the information at the idtechproducts link I provided a few posts up? This is certainly not the only magnetic stripe reader product, just the first found in a quick Google search.

"The UniMag is an encrypted magnetic stripe reader that works with various mobile devices. The UniMag reads up to 3 tracks of information with a single swipe in either direction, providing superior reading performance for your mobile device. A merchant account is required to accept credit card transactions. Mobile device not included."

I have the iMag Pro from http://www.idtechproducts.com/products/mobile-readers/112.html and it reads al kinds of cards. It ca nread 3 different strips. It will read my CA drivers licence, my credit cards, costco card, etc. Last time I stayed in a hotel with card entry keys it would read that too. I have not yet found a card with a mag strip on it that it won't read. So likely it would read your tradeshow badge, can't say for sure.

A few caveats:

Be aware that for the iMag pro the reader by itself is around $60-70 and that does not come with the SDK. To get the SDK, which comes on a CD, you need to buy the more expensive development kit (~$130 ) ten you can use that with as many readers as you like. The download link on therir website doesn't allow free SDK downloads.

I like the iMag Pro itself and the SDK is easy to work with , gives reliable results, but the hardware device itself needs better supporting plastic clips. The supoort clip they provide is specific for iPad 2 and won't fit iPad 1 (yes some folks still have those orginals) and may not fit whatever profile they have for iPad 3. The profile I refer to is the edge of the iPad itself which is tapered on iPad 2 but square on iPad 1. Also the device will not plug into most iOS devices when they have cases attached as the case gets in the way of the wide plug going in to the body of the iOS device. I see Apple is coming out with a new plug for the next rev of iPhone and iPad anyway so we will all have to buy new sets of cords and and adapters.

I got the unit and the SDK from IDTech. Do you know if it is possible to integrate with Actionscript 3 to get the info from the mag stripe using the iMag Pro? Any ideas on how to best tackle this?

SDK support for ActionScript seems unlikely. Does the SDK documentation indicate any language other than Objective-C is directly supported for iOS?

It is possible you could cobble something together by writing an AIR native extension iOS library in Objective-C that handles only the EAF communication, then call into that from your AIR app. I would not want to be the first person who tried to get that working. Doing everything in Objective-C is probably be much easier, and you would get better support from the IDTech.

http://www.adobe.com/devnet/air/articles/building-ane-ios-android-pt3.html