You can find whether an app is using flutter or not by using the following method,
Read moreHow do I know my project version Flutter?
You’ll see something like below in your terminal window: Doctor summary (to see all details, run flutter doctor -v): [✓] Flutter (Channel stable, 2.0. 3, on macOS 11.0. 1 20B50 darwin-x64, locale en-US) [✓] Android toolchain – develop for Android devices (Android SDK version 29.0.
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