First you need a personal key pair. Create one via the option menus in "My Keys" or import existing key pairs via "Import Keys". Afterwards, you can download your friends' keys or exchange them via QR Codes or NFC.
It is recommended that you install OI File Manager for enhanced file selection and Barcode Scanner to scan generated QR Codes. Clicking on the links will open Google Play Store or F-Droid for installation.
Please report the bug using the issue tracker of OpenPGP Keychain.
If you want to help us developing OpenPGP Keychain by contributing code follow our small guide on Github.
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