I'm mostly seeing 18%, 23%, 27% or variations of that which clearly seems to be a nudge towards the higher amount, relying on the social pressure of the server standing right over you holding the screen out to you vs the old way of leaving the booklet at your table to fill out after they've left.

In a more brazen example I've been promoted to take my seat and use a qr code to order, it then requires me to pay up front on my phone (while providing my PII in the form of an email and phone number), and then asks me to tip before I've even had a server so much as introduce themselves or bring me water.

I'm all for servers making a living wage and paying higher prices to support it, but the current path this seems to be taking is really an unpleasant experience as a customer.