Suprmind offers a multi-AI chat platform combining GPT, Claude, and Gemini...

https://extra-wiki.win/index.php/How_Do_@Mentions_Work_in_Suprmind_Like_@gpt%3F

Suprmind offers a multi-AI chat platform combining GPT, Claude, and Gemini models in one place. It costs $19 a month, undercutting ChatGPT Plus's $20 price