I'm an advanced industrial engineering student and I'm currently looking for some "final project" material. I have this idea of a product where you can plug in a type K thermocouple at the end of a meter long wire to your smartphone via the minijack port, as to mesure mainly kitchen-like temperatures (you know, how hot is the oven, is the meat ready, that kind of stuff) but it may also be used for other things. The concept would work initially for cooking and baking. It would need the output part of the minijack to get a steady and known electrical potential, and then to read the potential at the input part, where the difference found is proportional to the temperature measured. Can this be done? Can one get into writing and reading certain values of potential at the minijack port?
PS: I've got some basic knowledge of programming and null experience whatsoever with smartphone programming. If you can help me, please add links, references and material where I should look into and introduce myself further to the matter.