From discussion on Mastodon I understood that using OpenKeychain would have important advantages:

I don't have to worry about securely storing the private keys because OpenKeychain handles that for me
It also apparently supports NFC cards (like Yubikeys?)

Those are nice advantages, but there are some significant issues:

OpenKeychain is not under active development and seems essentially abandoned
It is not compatible with Android 14 OpenKeychain will stop working on Android 14 open-keychain/open-keychain#2836
Supposedly there are unaddressed vulnerabilities Vulnerability in OpenKeychain open-keychain/open-keychain#2856
It appears that you communicate with OpenKeychain via intents, so I assume any encryption/decryption would have to be done async. Ideally I want to do things synchronously.
The lack of an equivalent for iOS is a deal-breaker for Orgro

Support encryption #33

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