Thanks, I have just found out how to get it working. It involves changing settings on two different screens in the camera's setup interface:
1. Go to the "SD Recording" section and change the setting from avi to MP4 there.
2. Go to the "Audio and Video" section and change Video Profile 2 from H.264 to MPEG4. (I also upped the resolution to 640X480, FPS to 10 and bps to 384Kbps)
Now the IOS devices see and play the files
Hope this helps anyone else stuck with this.