Pi

Character.ai lets users chat with millions of user-created AI personas, from historical figures to original fictional characters. Its strength is immersive, in-character roleplay and entertainment rather than productivity. A massive community continuously creates and shares characters, making it one of the most engaging consumer AI platforms.

ChatGPT is OpenAI's flagship conversational AI, powering hundreds of millions of weekly users across web, mobile and API. Built on the GPT-4o and GPT-5 family of models, it handles text, images, voice and code in a single interface. With browsing, data analysis, custom GPTs and a vast plugin ecosystem, it remains the default assistant for most knowledge workers.

Claude is Anthropic's family of AI assistants, known for long-context reasoning, careful writing and strong coding ability. The Opus, Sonnet and Haiku tiers let you trade off intelligence, speed and cost. Claude excels at nuanced analysis, document understanding and agentic coding workflows, and is a favourite among developers and writers who value clarity.

Poe by Quora is an aggregator that gives access to dozens of AI models — including GPT, Claude, Gemini and many image models — through a single subscription. Users can chat with multiple bots, build custom bots and compare outputs side by side. It is ideal for people who want one place to reach many models without juggling separate accounts.