Compare AI tools

	Devin A	Perplexity S	NotebookLM S	DeepSeek S
Tagline	Cognition Labs' autonomous coding engineer.	AI search done right. Cited answers, not chat theater.	Google's research notebook. Turns your docs into a podcast.	Chinese open-weight powerhouse. Crazy cheap, genuinely smart.
Category	Agents	Research	Research	Chatbots
Pricing	$500/mo	Free + $20/mo Pro	Free	Free web + ultra-cheap API (~$0.14/M input tokens)
Best for	Engineering teams offloading tickets. Ops/platform work.	Replacing Google for any question where you want a cited answer in seconds.	Students, researchers, anyone with a stack of PDFs or a topic to learn.	Developers + cost-conscious builders. Anyone fine with self-hosting.
Strengths	Works like an engineer — takes Slack tasks, opens PRs Handles multi-hour engineering work Reports back with what it did	Sources every claim Fast, current answers Pro Search runs multi-step research Spaces for persistent context	Upload anything, ask questions, get cited answers Audio Overview turns docs into a 10-min podcast Great for studying	Open weights you can self-host Strong reasoning + math Near-free API pricing DeepSeek-V3 / R1 are serious models
Weaknesses	Expensive Best for well-scoped tasks Not for solo hobbyists	Not a general chatbot Answers can be shallow on complex topics	Google-only Can be slow on large corpora	Data goes to servers in China — privacy concerns for business use Chinese policy filters English polish trails Western models
Kai's verdict	A-tier for the right use case. Not for solo devs. If you manage engineers, try one license.	S-tier for search. I use it before Google now. If you're still Googling everything, try this for a week.	S-tier for study. The Audio Overview is a killer feature. Try it with three of your favorite PDFs.	S-tier for price/performance. A-tier for consumer use. If you build apps, this is the budget pick.
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