Apple will reportedly launch an "enormous" iPhone-related event in its retail stores this week in an effort to boost sales, 9to5Mac's Mark Gurman reports. Starting May 8, Apple will begin contacting those who are eligible for an iPhone upgrade via email. This means if you're using an older model such as an iPhone 4, 4s, or 5, you may be expecting a promotional email from Apple this week encouraging you to upgrade to a 5s or 5c.