You can add a paypal button, like "buy now" by simply generating a button in paypal and then copy and pasting the HTML code that paypal provides into an HTML section type in MyPhotoApp. For example:
<form action="https://www.paypal.com/cgi-bin/webscr" method="post">
<input type="hidden" name="cmd" value="_s-xclick">
<input type="hidden" name="hosted_button_id" value="dfkjdfkjdfkdf">
<input type="image" src="https://www.paypal.com/en_US/i/btn/btn_buynowCC_LG.gif" border="0" name="submit" alt="PayPal - The safer, easier way to pay online!">
<img alt="" border="0" src="https://www.paypal.com/en_US/i/scr/pixel.gif" width="1" height="1">
Available in Version 8.4:
If you want to have a form automatically go to paypal after people submit a form, you can do this:
(1) In the paypal html section, edit the form tag and add an id. For example, the above, just edit the first line like this:
<form action="https://www.paypal.com/cgi-bin/webscr" method="post" id="paypalButton">
You notice that I added id="paypalButton" to the statement. This adds an identifier, paypalButton that we can use.
(2) Now that we have an id that we can use to reference the button, go to the form you added and in the success url field, enter: paypal:paypalButton
The paypal: tells that you want the paypal button to be submitted. After the paypal: you specify the button id. It needs to match the name you put in step 1.