In general, if you remove your phone’s battery and see a little removable SIM chip, your phone is a GSM phone. If not, it’s a CDMA phone. On a GSM-capable iPhone, you can easily pop out the SIM tray as shown in the video here or as described by Apple here.
To make things a little confusing, though, LTE-capable CDMA phone also have SIM cards! But you generally don’t need to remove or change the SIM card from your LTE-capable CDMA phone in order to use it with Red Pocket Mobile.
For further reading on the subject, we suggest PC Magazine’s short article here.
For any further questions, please contact Red Pocket Mobile Customer Service toll-free 1-888-993-3888 or chat with us at Help.GoRedPocket.com (just type in your question first). We are here for you!