Article

An opinionated guide to which AI to use to do stuff

Ethan Mollick (One Useful Thing) · oneusefulthing.org

A Wharton professor's regular guide: any free model for low-stakes questions, ChatGPT or Claude for real work, and where Google, Copilot and voice fit.

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It answers 6 questions

  1. I'm new to AI. Which assistant should I start with: ChatGPT, Claude, Gemini, Copilot, Meta AI or another?
  2. Is the free version of ChatGPT, Claude or Gemini enough, or should I pay?
  3. Should I use more than one AI assistant, and can I move what one knows about me to another?
  4. How do I choose between a fast model and a thinking model inside ChatGPT, Claude or Gemini?
  5. Is voice mode worth using, and which AI phone app is best for talking to?
  6. Is the AI already inside WhatsApp or Microsoft Office good enough, or do I need a separate app?

Read with it

  1. Google's comparison of the free Gemini app with AI Plus, Pro and Ultra, including which plans get the stronger models. gemini.google Tool Google AI Pro & Ultra: get access to Gemini 4 Argon & more Google
  2. Survey of which assistants US adults use, from ChatGPT and Gemini to Copilot, Meta AI, Grok and Claude, broken down by age. pewresearch.org Article ChatGPT tops the list of chatbots Americans use, across age groups Pew Research Center
  3. Anthropic's comparison of Claude Free, Pro and Max, including memory, voice mode and the number of projects each plan allows. claude.com Tool Plans & pricing | Claude Anthropic
  4. Usage data on who uses which assistant, including how many ChatGPT users also use Gemini each week and India's place as a top... a16z.com Article The Top 100 Gen AI Consumer Apps, 6th Edition Andreessen Horowitz (a16z)
  5. OpenAI's own table of Free, Go, Plus and Pro: what each includes, from GPT-6 chats and memory to voice, projects and deep... chatgpt.com Tool ChatGPT Plans and Pricing OpenAI
  6. What Copilot does inside Word, Excel, PowerPoint and Outlook on each Microsoft 365 plan, against the free version. microsoft.com Tool Microsoft Copilot Plans for Individuals Microsoft
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