What it does: Uses Large Language Models (LLMs) to search the abstracts and, when available, full text of articles to find the 4 “best” sources in the free version.  It compares and summarizes them.  It also has a feature allowing users to upload and interact with the PDFs of full text articles.
Cost: Free with paid tiers
Citation Tool Integration: Citations can be exported to Zotero
FAQs (scroll to bottom of page): Elicit: The AI Research Assistant
Privacy: Elicit: The AI Research Assistant

Considerations:

• Pulls from Semantic Scholar.  It may only be accessing abstracts to some sources.
• Hallucinations can still occur so all results should be verified by consulting the original source.
• Works on research where numerical data best answers the question.
• Elicit requires an account to try it out. 

The video above demonstrates how to use Elicit.  Some of the features demonstrated may be associated with a paid tier.