Android

If you want to add a payment method:

1. Open the Google Play Store app.
2. In the top right corner, tap on the profile icon.
3. Go to "Payments and subscriptions" > "Payment methods" > "Add payment method".
4. Select the payment method you wish to add and enter the information requested.

If you wish to edit a payment method:

1. Open the Google Play Store app.
2. In the top right corner, tap on the profile icon.
3. Go to "Payments & subscriptions" > "Payment methods" > "More" > "Payment settings" (You may be prompted to log in.)
4. Select your preferred payment method and click "Edit".
5. Once you have made the appropriate changes, tap on "Update".

If you wish to remove a payment method:

1. Open the Google Play Store app.
2. In the top right corner, tap on the profile icon.
3. Go to "Payments and subscriptions" > "Payment methods" > "More" > "Payment settings" (you may be asked to log in).
4. On the payment method you wish, tap on "Remove".

iOS

To change your payment information, follow these steps:

1. Open the "Settings" app.
2. Tap on your name and then "Payment & Shipping" (you may be prompted to log in).

To add a payment method:

1. Select "Add payment method".
2. Enter the details of the card you wish to add.

If you wish to update the payment method:

1. Tap on the one you wish to modify.
2. Edit the corresponding information.
3. If you see Apple Pay after the last 4 digits, go to the Wallet app to edit the card information.

To remove a payment method:

1. Tap on the payment method you wish to remove.
2. Select "Remove payment method" under the shipping address.

If you want to change the order of the payment methods:

1. Tap on "Modify" in the top right corner of the screen.
2. Sort the payment methods as you see fit.