Android only installs an update signed by the same key as the version already on your device. This timeline shows every signing key we've seen for Mail: Email, Cloud, Calendar. One known signing key across every release we hold.
15.96.0.143126
Current key1 release · Jul 28, 2026Every key we have ever recorded for Mail: Email, Cloud, Calendar. New builds are compared against this set; a build signed by none of them is what our badge calls a mismatch.