Provide SHA-256 Hash of Signing Certificate

[TheBrambleShark]

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Pre-Submission checklist

• There is no existing issue that already asks for this feature.
  
• The feature already exists in rclone (on your PC or in Termux)
• I am prepared to help make this feature

What version of RCX are you using (About -> App version)?

Any/All

What problem are you trying to solve?

I would like to be able to install RCX through Obtanium and verify the signed .APK file with AppVerifier.

What should RCX be able to do differently to help with this problem?

In the project readme or in the release notes for each release, please provide the package name and SHA-256 hash of the signing certificate.

This can be obtained by using the apksigner tool. The below example is provided by AppVerifier:

> apksigner verify --print-certs AppVerifier-X.Y.Z.apk
dev.soupslurpr.appverifier
3A:04:A8:0B:2A:88:33:4C:74:74:85:F0:B2:15:16:40:A3:8B:B3:D2:D7:3A:8E:AB:81:DF:50:3E:0F:02:02:B2

This information can be copied and pasted into AppVerifier to ensure the apk file that was downloaded was signed by the developer and has not been modified.

Ideally, I'd like to see this app available on Accrescent, which would avoid all of this, but their app submissions are closed currently.