Poly Duo

For the first time, your own ChatGPT and Claude apps work together on your phone — one tap, free. Any AI can sound sure and still be wrong, and checking by hand means pasting the question into a second app and comparing two walls of text. Poly Duo does it in one tap. ChatGPT answers, Claude answers on its own without seeing the first answer, then the two are compared. In about a minute, via Action Button, Siri or Back Tap, you get three blocks: where they agree, where they differ, and what is worth checking yourself. It is an iPhone shortcut (iOS 18+) built on the official actions of the ChatGPT and Claude apps, so free accounts are enough; the question goes straight to your own apps. The code is open: https://github.com/vadimchernets/poly-duo. There is also a separate free Poly app for Android on Google Play. Why it is new: on computers, tools that ask several models at once existed, mostly browser extensions and paid hubs. On a phone, free and with nothing in between, there was nothing like it. The number behind it: on 100 new questions the two flagship models agreed 74 times and were right 72 of those times; the 26 disagreements are where a human should look (October 2026, GPT-6.1 Sol and Claude Opus 5.5). I can send an 18-second demo and screenshots. One-tap install and video: https://polyhelper.ai/duo/?ref=us-startuplist Developer: Vadym Chernets, AI researcher whose research was accepted at NeurIPS 2026. info@polyhelper.ai