There was an update sometime last month indicating that Microsoft doesn't keep the photos after the security experts had found out that the photos were stored in some Azure database that was used in HowOld.net service. It was a shameful move from Microsoft but it was either experimental or not expected. Even then, there was some serious security controversy regarding that service that would take you back to when the new Kinect device was being planned. And in fact, it wasn't even techniaclly excusable to indicate that improvements to HowOld.net service were on the way for more accuracy on age detection over security flaws.
Then, there's TwinsOrNot.net and for whatever reason, things may be much more challenging than HowOld.net to implement as an experiment or something. And guess how long it took to develop, weeks or perhaps months? NO, IT'S 4 HOURS on this web service alone and Nintendo came out with something like this years ago! But it doesn't matter who came out with something like this the earliest, does it? If it doesn't matter, this is the great time to try this web service out.