ChatGPT falls below 50% market share as rivals Google Gemini and Anthropic gain ground

ChatGPT market share Google Gemini Anthropic Claude Sensor Tower report

Sensor Tower’s State of AI 2026 report shows that global time spent on generative‑AI apps is set to double, reaching about 36 billion hours in the first half of 2026. The report also notes that ChatGPT became the fastest mobile app to hit one billion monthly active users, but its “True Audience” share slipped below 50% for the first time in March 2026, now standing at roughly 46.4%.

Competing assistants are closing the gap: Google’s Gemini accounts for about 27.7% of AI‑assistant usage, while Anthropic’s Claude holds roughly 10.3%. Other chatbots such as Grok and Meta AI each remain under 5%. Despite the share loss, ChatGPT still leads with about 1.1 billion monthly users. The market remains heavily concentrated, with ChatGPT, Gemini and Claude together representing nearly 90% of total engagement.

The report highlights parallel trends of rising consumer spending on AI apps, projected in‑app purchase revenue of over $4 billion in H1 2026, and a surge in AI‑related app downloads and advertising spend. These dynamics underscore the growing commercial value of AI assistants across shopping, advertising, and app development.

Sources

Sensor Tower State of AI 2026 Report: Global Time Spent on Generative AI Apps Projected to More Than Double Year-Over-Year | The AI Journal [aijourn.com]