It's free for you, forever! Launch the app, sign up, and set up your Ready account once, then it's only two taps to pay your restaurant bill, every time. Pull up the Ready App whenever you are ready to pay. Simple!
The Ready Team releases updates to the app regularly without you needing to do a single thing. If it looks like your friend's Ready App has new features that is missing in yours, try rebooting your app. Occasionally Ready will ask you to update the app from your App Store, but we'll do our best not to bug you with silly tasks like that.