If you are using a computer right now, (and while I do not believe I have psychic powers, I do believe you are using one right now), the technology that is used to read your hard drive may soon be used to detect disease in your body and contaminants in the environment.
The principal (which won a Nobel Prize for its discovery) is called giant magnetoresistance or GMR and the process of testing would be simple. Like swiping a credit card at a grocery store, one would simply swipe a card laced with samples of blood or other biological substance through a card reader. Signatures of disease would then be noticed by sensors and results would be ready in minutes as opposed to days.
Utah Science Technology and Research (USTAR) professor of chemistry, chemical engineering and bioengineering, Marc Porter, believes there are many applications but foresees this being used to monitor health on an ongoing basis. Once a baseline for health was established for people, they could re-test at specific intervals in the future, perhaps even at home.
Perhaps the results could then be sent to an iPhone?