ChatGPT

ChatGPT is a general-purpose conversational AI that handles research, writing, coding, brainstorming, and more. The free tier uses GPT-3.5 (decent), Plus ($20/month) unlocks GPT-4 (significantly better reasoning and accuracy). You chat with it like a knowledgeable assistant who can draft emails, debug code, explain concepts, and generate ideas. Web browsing and image generation (DALL-E 3) included in Plus.

Best for knowledge workers who need an AI assistant across multiple domains — founders drafting strategy docs, developers debugging code, marketers writing copy, students researching topics. It's the Swiss Army knife of AI tools. If you only subscribe to one AI tool, this is it. GPT-4 quality justifies the Plus subscription if you use it daily.

Where it's not ideal: lacks context of your specific codebase or company (use Cursor or Claude Projects for that), can confidently state incorrect information (always verify critical facts), and free tier (GPT-3.5) is noticeably worse than Plus. For specialized tasks, domain-specific tools (Jasper for marketing, Copilot for code) may be better. But for general intelligence and versatility, ChatGPT is the baseline.