Below are the steps to setup Square credit card processing with PHP Point Of Sale iOS

1. Signup to be a merchant with Square
2. Download the Square App and pair your credit card reader if necessary
3. Download PHP Point Of Sale app on App Store or Download on Google Play
4. Login to PHP Point Of Sale and click locations
5. Scroll towards the bottom and check the box "Enable Credit Card Processing"
6. If you are using a currency other than USD; make sure to type it in the Currency input field
7. You shouldn't change Multiplier to get total in cents unless you have a different currency that has this
8. Create a sale and choose payment type of credit card
9. Click process credit card. You will be directed to the square app to complete the transaction and then redirect back to the POS when done