To create a per-product commissioning structure with iDevAffiliate and Gravity Forms, all you need to do is define the commission rate for each form you create.
When you create your form, you will add a pricing field to it and will use a Field Label for it like normal. In this case, you can see in the image below, we’re using a Field Label of test_product and a price of 19.99.
In your iDevAffiliate admin center, go to Commission Settings > Per-Product Commissioning. On the Add A Product tab, you will use the same Field Label created in Gravity Forms as your Product Identifier and enter in Product Amount (same price created for the product). Now just define your Commission Amount for this product and you’re all set.
In short, all you need to do is use the Field Label number defined in Gravity Forms as your Product Identifier in iDevAffiliate. Anytime this product is purchased, the per-product commissioning override will kick-in and use the defined Commission Amount for the product.