Which retail innovation first allowed dictionary publishers to offer real-time language updates to consumers without requiring new physical product purchases?

The world of dictionaries and language reference tools has undergone significant transformation in the digital age. New retail innovations have changed how we access, use, and purchase language resources. This trivia question explores a groundbreaking retail innovation that revolutionized how consumers interact with language products. Test your knowledge of the intersection between retail innovation and linguistics!

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Subscription-based online dictionaries with continuous updates (introduced by Oxford Dictionaries Online in 2000)
Interactive CD-ROM dictionaries with quarterly mailed update discs (pioneered by Merriam-Webster in 1996)
Print dictionaries with QR codes linking to supplemental word lists (launched by Collins in 2008)
Dictionary mobile apps with annual paid upgrade packages (first released by American Heritage in 2005)