Perplexity

Perplexity is an AI answer engine: instead of a list of links, it searches the live web and returns a concise answer with clickable citations for every claim. That citation-first, real-time approach makes it a natural research assistant — its agentic Pro Search and Deep Research can break a complex question into steps, run multiple searches, and compile a sourced summary. You can switch among top models in one interface, and both a usable free tier and a free AI browser (Comet) lower the barrier to entry.

The tradeoffs are focus and trust. It is deliberately narrow — an answer engine, not a general assistant or workflow tool — so at its price it competes with ChatGPT and Claude, which do more. Its answers are cited but not infallible (independent audits have flagged real error rates), so verify before relying, and on free and Pro tiers your data may be used for training. For sourced research it is best in class; for everything else, a general assistant may fit better.