OpenAI's ChatGPT app is experiencing a slowdown in growth, with a decline in daily active users noted around late August and early September. The average time spent in the app has decreased by 22.5% since July, and there has been a 20.7% drop in average sessions. This suggests users are engaging less frequently and spending less time per visit. Factors contributing to this trend include competition from newer models released by companies like Anthropic and Google, dissatisfaction with OpenAI's GPT-5 model, and the conclusion of an initial phase of experimentation by users. OpenAI has announced changes, such as introducing capabilities for generating "adult" content, to attract new users.