Perplexity.ai is the best, without question beats ChatGPT. You can setup GPT-4 for ChatGPT answers, but it requires an account. Thankfully they accept alias email address for accounts. Regardless of GPT-4, the site always provides filters like all or academic and also provides sources for any provided information. It is the only way I use AI!
Edit: Perplexity also offers a conscience explanation by default but you can ask for a detailed explanation as well. It's the bee's knee's
www.phind.com - it's a combo AI + search engine geared towards developers. You get the AI answer and the search engine answer side-by-side, and the AI answer will cite it's sources for you to investigate/verify what it's telling you