Nothing new about it. It's the same polished up turd that was around 3 years ago. It is just a lot easier to track a person via cellphone now then it was 2 or 3 years ago.
If you read the whole thing, it tells you at the bottom that the only number it can/will track is YOUR number. If you're with someone else, showing them the new app, you put in their number (apparently you can put any number you want in it, but it tracks only YOURS)... but since you're standing right there... duh.