Hi folks, I’m more than happy to share my development on supporting Google/Apple pay, this is gonna be an open-source contribution instead of a paid extension! Please refer to my pull request for more detail: tastyigniter/ti-ext-payregister#43
TL; DR. The work is done by integrating Stripe Checkout, which is a checkout page built by Stripe.
I have listed some technical details as well as a Pros&Cons analysis in the pull request. Any suggestions or comments to be very appreciated! And if you have a GitHub account, I would enjoy your support by giving me a little rocket reaction in the PR.