They feel different in the hand, and the web versions do not tell you that. ChatGPT app vs Claude app is the best mobile AI assistant question I get; both are free and excellent, so the choice is about fit, not quality. - The ChatGPT app is the fuller product: voice conversations, image questions, the broadest ecosystem. For phone-first users, that depth matters. - The Claude app is the calmer product: cleaner interface, better long-form writing, a feel that stays out of your way. For writing-heavy phone work, calm beats depth. - Test the same way: dictate a message while walking, photograph a document, draft something you would send. Score accuracy and enjoyment. The app you reach for without thinking is the winner. Most people end up with ChatGPT as the daily driver and Claude for writing-heavy days. StackAudit recommends the optimal 3 to 5 tool AI stack for your profession with pricing and setup guides for $4.99 one-time unlock.