NY POST - Nov 15 - The Grade, a free matchmaking app that launched this week by Snap Interactive, uses an algorithm to boot users with bad grammar and dirty messages. It ranks profiles A+ to F based on popularity, message quality and response times. Like Tinder, The Grade users swipe right to like a profile. If two users match, they can begin messaging. But daters with a D grade get a warning, and daters with an F are bounced.