If you want an AI chat interface that can help you generate content and ask questions, ChatGPT is a great option. It's got a basic interface that can help you with a lot of things, like answering questions, generating ideas and getting more work done. It's free to use with no subscription or payment required, so it's a good option for quick needs.
Another good option is OpenAI, which offers a more general-purpose artificial general intelligence service. OpenAI includes ChatGPT, but also can generate images, process data and chat by voice and text. It's customizable and offers a range of pricing options, including a free version with limited access to GPT-3.5 and GPT-4 models. It's also geared for enterprise customers with more-advanced models and analysis, so it's good for a broader range of needs.
If you're looking for a more specialized answer engine, Perplexity offers a service that offers authoritative, trustworthy answers in real time. It's multilingual and offers a free tier with limited usage, but a Pro tier with unlimited Pro searches and large language model AI models costs $20 per month. It's geared for individuals, researchers and professionals who need a reliable source of information.
Last, BrainyAI is a browser sidebar tool that combines AI chat, search and summarization abilities. It uses multiple AI models, letting you chat with multiple AI engines at the same time and compare results. It's designed to help you work more efficiently with immediate answers and to summarize documents, so it's a good tool for research and writing.