Elicit is an AI research assistant that can find papers, summarize them and extract data from more than 125 million research papers. It's geared for data-intensive subjects like biomedicine and machine learning, and can automate tasks like systematic reviews and meta-analyses. You can upload your own papers for processing, too, and there are several pricing tiers.
Another option is Scholarcy, which converts academic documents into interactive summary flashcards and offers more advanced features like customizable summaries, notes and highlighting. It's geared for students and researchers trying to get a better handle on complex information, and offers free and paid options.
If you want a quick summary service, SummarizePaper uses AI to summarize papers from arXiv. You can search for papers, ask natural language questions and get an immediate response. It's free and maintained by an astrophysics researcher who wants to make research accessible to anyone.
Finally, Semantic Scholar provides a more general AI-powered research service with tools to filter and summarize papers. It also offers features like AI-generated definitions, paper recommendations and the ability to set up automated email alerts for new citations. It's free for researchers and developers, and new features are added all the time.