Help "button" on back

[tommytebco]

I just bought an Amzer snap case ofr my phone (from Amazon)

The case has a hole in the back/bottom that corresponds to a button looking thing at the bottom of the rear.

Nothing in the literature mentions the thing. But the hole in the case suggests it might actually have function.

Anyone know what it is??

 

[thangfish]

External antenna jack.
I've actually been wanting to try it, to see if I could get better data speeds at home, but the place I found to order antennas has you specify which plug you want and I couldn't be certain which one to order.