How to Use a Phone As a Credit Card Terminal. If you have a smartphone -- be it an iPhone or an Android-powered phone -- you can use a portable card reader to take credit card payments anywhere ...

Tap your phone on the reader at the cash register, and like magic, you’re done. The charge will be processed using the debit or credit card you entered into your digital wallet.

As many Android phones lack SD card slots, reading such cards requires an SD card reader. We've compiled a list recommended by users to help you out.