Just in case anyone else has a similar problem. I was selecting the photos on my iphone then emailing them to myself and saving from the email. Seems that it was stripping the geotag during that process.
If I plug my iphone in and navigate to the photos copy them and put them in a folder it work's fine.
Chris thanks for your help with this, especially as I suspect you knew it wasn't an ESRI problem from the start!