KFC's Tray Typer keeps you clicking even with greasy fingers

KFC's Tray Typer keeps you clicking even with greasy fingers:

Horror of horrors, you've just downed a plate of Colonel Sander's famous fried chicken only to have that text you've been waiting for suddenly ping your phone. What do you do? Clearly the answer isn't to reach for the napkins. No, instead you do what...