Timothy didn't like my implanted iPhone idea at all. But in a few years time this will be much less invasive than a hip replacement, fillings, surgery to correct eyesight or a pacemaker, and we all accept these things as being anything from useful through to necessary.
In fact, check out this artificial heart. For some reason I especially like the bit in that linked article that says "In this article, you will get an in-depth look at how this new artificial heart works, how it's implanted into a patient's chest and who might be a candidate for receiving one of these mechanical hearts. We will also compare the AbioCor heart to the artificial hearts that have failed in the past."
If you had to get one of those suckers, or pumpers, you might as well get the scaled down wireless iPhone equivalent of 5 years from now implanted along with it.
In a short while I would say that my iPhone implant idea will be able to be powered by a person's body movement.