Mobile Banking Apps

I work at a credit union, so we hear a lot of buzz about mobile banking- who has it, who hates it, etc. One of the things that consistently amazes me is the development of remote deposit programs. From what I understand, banks and credit unions are rolling out programs that allow you to scan an image of your check and electronically deposit it into your account. It's a great timesaver, but I can't figure it out.
MICR is what is used on checks for identification and verification, and the ink uses a magnetically-oriented printing process to be secure. It's expensive, and it's technically detailed, but more importantly, I always though it required a proprietary reader (something that could detect the magnetism) to be truly guaranteed.

Has anybody worked with these mobile apps? Has anybody used them or developed them? How are they working? Does anyone know of any open-source projects that are using them?

Looking forward to your insight,
A.