What's the version? If one is newer than the other that maybe the difference
the reader I used worked on both.
I do not know what version. I got it well in advance of Oct 1. It never "connected". Now that I know the problem (the original gizmo worked fine in the iPhone), it is not a problem.
.
What version iPhone vs. what version iPad? -- the chip-reader device won't work with older version phones or tablets (you can check the square site for a list of compatible devices). Alternatively, have you downloaded and installed the latest version of the Square register app on the phone? I think I had to not just "update," but "uninstall" the old version and then "install" the latest version. Also, in terms of getting it plugged in to your phone, if you have a cover or case for your phone, it may be that which is causing the problem-- If you take the phone out of the case, you should be able to plug the reader device all the way in (which would suggest maybe getting a new case that has a larger opening around the earphone jack). This is all assuming you want to be able to use the new reader on your phone as well as on your iPad...
.