Anthropic’s Claude app had about 2.1 million monthly active users in South Korea in October 2026, about 15 times the roughly 140,000 of a year earlier, according to app-analytics firm IGAWorks Mobile Index, as reported by the Korean daily Hankyung (Hankyung, November 8). Claude moved from seventh to second among AI apps by users.
OpenAI’s ChatGPT app passed 18 million monthly users in Korea for the first time: Mobile Index counted 18,762,276 in October, up 43.8% from 13,048,025 a year earlier. The figures cover Android and iOS apps only, not web use.
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The key insight: IGAWorks Mobile Index data reported by Hankyung shows Claude’s Korean app users rose about 15 times in a year to about 2.1 million, while ChatGPT’s passed 18 million and held about 91% of AI app users.
According to Hankyung’s report of the Mobile Index data, total ChatGPT app usage time in October was about 50.98 million hours, up 113.9% from about 23.83 million hours a year earlier. Average monthly use per person rose from about 110 minutes to 163 minutes.
Mobile Index puts ChatGPT’s share of AI app users at about 91% in October 2026, up from about 84% in October 2025. ChatGPT also led new installs with about 790,000 in October, though that was 16.2% fewer than a year earlier.
For Claude, Mobile Index reports total usage time of about 3.88 million hours in October, 22 times the level a year earlier, and about 490,000 new installs, about 13 times a year earlier and second after ChatGPT.
Monthly active users of the ChatGPT and Claude mobile apps in South Korea in October 2025 and October 2026, from IGAWorks Mobile Index as reported by Hankyung. Android and iOS apps only; web use is not counted. Claude figures are approximate. The ratios in the title are our arithmetic.
By our arithmetic, ChatGPT’s app had about 93 times as many Korean monthly users as Claude’s in October 2025 (13.05 million against about 140,000), and about 8.9 times as many in October 2026 (18.76 million against about 2.1 million). In absolute terms ChatGPT still added more users over the year: about 5.71 million, against about 1.96 million for Claude.
Also by our arithmetic, Claude’s reported usage time works out to about 111 minutes per monthly user in October (3.88 million hours across about 2.1 million users), against 163 minutes for ChatGPT.
The Structural Read
As we read the Mobile Index figures, ChatGPT still dominates Korean AI app use: about 91% of AI app users, and about 2.9 times as many added users as Claude over the year, by our arithmetic (about 5.71 million against about 1.96 million).
As we read it, Claude’s gains show in installs as well as users: about 490,000 new installs in October, about 13 times a year earlier, while ChatGPT’s installs fell 16.2%.
As we read the usage-time data, ChatGPT users are spending longer in the app: average monthly use rose from about 110 to 163 minutes, and total hours more than doubled.
Hankyung, reporting IGAWorks Mobile Index data (our translation)
“Usage time rose more steeply than the number of users”
Three Implications
FOR OPENAI Mobile Index counts 18,762,276 monthly ChatGPT app users in Korea in October, up 43.8% in a year.
FOR ANTHROPIC Mobile Index puts Claude second among AI apps in Korea by users, up from seventh previously.
FOR READING THE DATA The figures count Android and iOS apps only and do not include web use.
The analysis says: “Every AI paradigm produces a different kind of moat.”
As we read it, app-user counts like Mobile Index’s measure reach, not which of these moats a lab holds. The analysis does not discuss Korea or app usage.
What Is Not Established
We read the Mobile Index figures as reported by Hankyung, in our translation; we did not read a Mobile Index release directly. The Claude figures are given as approximate. The report counts mobile apps only, so web and API use is not included. It does not give figures for Gemini, Perplexity or Korean apps in this report. App users are not paying subscribers, and the data says nothing about revenue.
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Mobile Index data shows ChatGPT passing 18 million monthly app users in South Korea and holding about 91% of AI app users, while Claude’s app grew about 15 times in a year to about 2.1 million and moved to second place. By our arithmetic, ChatGPT’s lead in app users narrowed from about 93 times to about 8.9 times.
A note on sourcing. Figures are IGAWorks Mobile Index data as reported by Hankyung on November 8, 2026, in our translation from Korean. They cover Android and iOS apps only. The ratios are our arithmetic. This piece is not investment advice.
Gennaro Cuofano is a CRO and tech executive who has worked in AI since late 2015, starting with bringing NLP, natural-language generation, voice and chatbot products to the marketing industry. His background is in law and finance: he holds a Master's degree in Law and an International MBA with an emphasis on corporate finance (LUISS Business School and the University of San Diego, 2012), and worked as a financial analyst at a real-estate investment firm in San Diego and as an assistant controller. His work focuses on business model strategy, business engineering and, more broadly, structural analysis: how companies make money, read from their own filings. He created FourWeekMBA and leads research there and at The Business Engineer, his newsletter on AI and business strategy, with over 95,000 subscribers and more than 1,000 published analyses. His writing has also appeared on Entrepreneur (for example, How to Digitize a Family Business in Europe) and HackerNoon. Find him on LinkedIn and Substack. See how we source.
