The act of sending multiple text messages to someone without receiving a reply, causing the visible range of the iphone text message (sms) screen to be filled solely with gray message bubbles.
Note: The accumulation of texts causing a "gray screen" can occur over minutes, hours, or days; as long as the consecutive stream or thread of messages (multiple gray message bubbles) is uninterrupted by the recipient sending a reply (green message bubble)
Hudson: You know that girl I met at Dan's Cafe Friday night?
Hudson: Well, she totally gray screened me last night.
David: Dude...sounds like a clinger to me.
Hudson: Yeah, stage nine.
This girl has been gray screening the hell out of me!