Commented on Poly Duo (C1M) · Oct 25, 2026
C1M Duo turns one habit into one tap: ask ChatGPT, then have Claude check the answer. On iOS 18 both apps publish Shortcuts actions — Ask ChatGPT and Ask Claude. Duo chains them, so it runs on your own accounts: no server, no API keys, no proxy. Free accounts work; with Plus or Pro you get the strongest models of two companies working together at no extra cost. The result opens with where the two agree, where they differ and what to check yourself. Under the hood: one shortcut routes 12 modes, prompts are plain files in locales/, and tools/verify.py checks the signed shortcut against the sources. 11 languages, Apache-2.0. This has existed on computers. On a phone, free, with nothing in between — not until now. Which mode would you add next? — Vadym Chernets, independent AI researcher (PhD); two posters on AI evaluation and verification at NeurIPS 2026 workshops: https://neurips.cc/virtual/2026/178299 · https://neurips.cc/virtual/2026/loc/sydney/173020
