Founder of Two Tap here. It takes an average of three minutes to send the order to the retailer via our platform. On the frontend we use a similar model to Amazon where tell the shopper we're confirming her purchase and handle the process in the background. It's working great for Amazon, and it works great for us for a thousand merchants.

Retailers are incredibly happy by the fact that they don't have to do a complicated integration where they have to maintain a new piece of infrastructure for potentially getting less than 1% of their orders.

That being said, we're huge fans of Stripe. Always have been. John Collison was our mentor during YC. We're looking forward to seeing how they handle the challenges in the space.