We have a custom Android applicatoin that we use on mobile devices to check people in to our system.  It communicates with a local Windows server via web services.  We would like to be able to take payments on the mobile device in the following way:

• Person walks up to someone with our mobile check-in device.
• Employee swipes credit card for a set pre-authorization amount.
• Android device sends card data to local webserver via web services (C#).
• Local server runs pre-authorization on authorize.net and responds to android device with success/fail.

My question is, how best to accomplish this?  We do not want the mobile devices talking with Authorize.net directly (they don't have internet access).  We need to remain PCI compliant.  Is there a swiper that will encrypt data in a way that authorize.net will accept encrypted or do we need to use a swiper that will give us unencrypted track1/track2 data to send to authorize.net?  I just bought a uDynamo swiper and it looks like the Android SDK will give me encrypted data - but it looks like authroize.net wants the data decrypted.

All suggestions are welcome.

Thanks!

Brett Jones