Our checkouts have excellent UX and are industry-leading in their conversion rates. You may notice minor changes to user flow/user interface while working with Paddle, as we actively A/B test the checkout across several variants, iterate to improve conversion further, and help our sellers make more money.
You can make minor changes like adding a brand color to the overlay checkout on the Checkout Settings page under the “Overlay” tab.
If you would like further customizability of the checkout, we recommend that you implement our inline checkout instead, which allows you to fine-tune far more aspects of the checkout under the "Inline" tab.