Gemini 3.5 Flash becomes the default across Google’s assistant

Google introduced Gemini 3.5 Flash on 19 May, beginning a new model family with a release available through the Gemini app and AI Mode in Search. Its announcement also listed access through Antigravity, the Gemini API, AI Studio, Android Studio and enterprise services.

Google made Flash the default model for Gemini and AI Mode globally. It described improved coding and longer agent tasks, supported by benchmark results reported in its own announcement. Gemini 3.5 Pro was still being used internally and was presented as a later release.

Gemini Spark, a personal agent powered by Flash, started with trusted testers. Google planned a US beta for AI Ultra subscribers the following week. That difference in access is central to the launch: a broadly available model could power a service whose ability to act for a user was still being introduced to a much smaller group. Consumers and developers were entering different parts of that rollout.