I got a follow up email shortly after with subject: "Did you order the correct case?" The case I ordered specifically said that it was good for any number of smartphones, but I double checked the product listing because maybe I was supposed to check a box.
But I was correct, so I replied back to the email that I was sure I got the right one. I received an email shortly after that confirmed I made the right purchase.
In my opinion, this particular email needs to be updated. Since the phone case fits ANY smart phone, there shouldn't too much confusion on picking the right one. I noticed that on the menu page on the home screen, there are several choices for cases on any number of phones, but they all seem to take you to the same product listing. The phone case is a one-size-fits-all, as far as I can tell.
However, the tablet cases are all different. There seems to be a different case for each brand and size of tablet / iPad. So for sure, you want to make sure that the customer is getting the right case, especially since the customer may not know the exact make and model of tablet they own.
So if I were to rewrite the "did you order the right product" email, I'd have at least two versions. One that goes out if you bought a phone case: "hey, you bought a phone case, this will fit any smart phone, but it WON'T fit a tablet or iPad. If you meant to get an iPad case, reply back in 60 minutes."
Then if the customer bought an iPad case, the email could be like, "you bought a case for the iPad mini. That case is made ONLY for the iPad mini. We make several versions of that case, so make sure you got the right one. If you're not sure, or if you made the wrong choice, reply back in 60 minutes." Best practice would be to send out a specific email for each tablet case, to better fine tune the process, but that goes up in the air if the customer buys more than one case.