 Re: One authenticator app for multiple accounts?
There is no communication between Authenticator and the "outside" world. The app is basically a QR code scanner + a calculator that displays output with the QR code and time as the input (i.e. the private key + public key stuff).
If you are still in doubt (or you don't have a smartphone and don't intend to buy one), then theoretically you can read some academic paper, learn to "read" the QR code with eyeball and do the calculation with Excel.
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