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Typing these four characters could crash your iPhone | TechCrunch
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This is not a kernel panic and associated reboot. It simply crashes the SpringBoard, which is kinda like the "desktop environment" of iOS. It's responsible for the homescreen, and calls other processes like the window server. It's a normal userspace process, not related to the kernel at all.
Edit: Sorry I actually meant to link to this wiki page https://www.theiphonewiki.com/wiki//System/Library/CoreServices/SpringBoard.app