The title is not the original and is misleading: The smartphone measures glucose in a gel containing minuscule magnetic particles in a small container near the phone's magnetometer. As the gel reacts, it moves and this displacement is detected by the phone.<p>So it was never intended to measure glucose in the blood of a living creature.<p>It seems to me the innovation is:<p>1. in making the phone directly measure the amount of glucose<p>2. in inventing a gel that reacts to the presence of glucose by expanding or contracting.<p>Indeed as stated in the article, they could measure other things than glucose, it's just a matter of using other nano-particles