Official line
Replaced by Messages in OS X Mountain Lion.
Apple · Messaging · Product
iChat
Discontinued
2002–2012 · 10 years in market
Launched
Aug 24, 2002
Discontinued
Feb 16, 2012
Cause of death
Replaced by successor
Evidence
Unsourced
What was it?
Bonjour and AIM bubbles on the Mac. Became Messages when iMessage needed a desktop home.
Why it died
Editorial reading
The center of gravity moved from AIM to iMessage. The bubbles stayed; the protocol did not.
Founder takeaway
Chat clients are protocols in a trench coat. When the network changes, the coat gets a new label.
Sources
Unsourced — editorial reading
No primary source is attached yet. Treat the interpretation as editorial, not a citation.
What replaced it
Apple
Messages
iMessage on the Mac.
Related graves
Same company, category, or cause of death.
Apple
RIP
iWork.com
2009–2012 · 3 yrs
Apple’s early document-sharing beta for Pages, Numbers, and Keynote. Folded when iCloud arrived.
Productivity/Replaced by successor+31
Apple
RIP
MobileMe
2008–2012 · 4 yrs
Apple’s first real cloud suite. Launched broken, lived embarrassed, replaced by iCloud.
Cloud & Infra/Replaced by successor+31
Apple
RIP
iPod touch
2007–2022 · 15 yrs
iOS without a phone plan. The last iPod, killed when a cheap iPhone became the honest version of the same idea.
Hardware/Replaced by successor+31
Apple
Feature
RIP
Dashboard
2005–2019 · 14 yrs
A full-screen overlay of widgets. Replaced by Notification Center, then by the modern widget panel.
Productivity/Replaced by successor+31