Downloaded app, clicked "Install" but install then fails with message "Failed to Install".
User should be able to install app.
1) Download edX app on android version 5.0.2
2) Click "Install" and view.
This is probably just because the signing key was wrong and the user still had the release version installed.
can you please retest with latest build? can you provide the latest build?
Verified on device with android version 5.0.2, Its working fine.