Install failed: cannot downgrade to an older version
INSTALL_FAILED_VERSION_DOWNGRADE
The version you are installing is older than the one already installed, and Android refuses downgrades unless the installer explicitly asks for one.
Why it happens
Android compares versionCode. If the incoming package has a lower number than the installed app, the install is rejected by default. The rule is separate from the one that allows replacing an app — which is why enabling “Replace existing” does not help here, a point that trips up almost everyone who hits this.
How to fix it
1. Turn on Allow downgrade
A privileged installer can pass the downgrade flag. In Universal Installer this is Allow downgrade in the Shizuku or Root options, and it needs one of those modes — the default system installer has no equivalent.
2. Uninstall the newer version first
Works in any mode and needs no special setup, but the app's data is lost.
3. Expect data problems either way
An app that has already migrated its database to a newer schema may not start on an older build, even when the install itself succeeds.
Also shown as
- Can't install older version of app
- downgrade not allowed
- INSTALL_FAILED_UPDATE_INCOMPATIBLE downgrade