From version 5.6.6-210928.0.1:
Being an integral part of the MIUI software ecosystem, Security contains a powerful set of protection and optimization tools. App lock, Data usage, Security scan, Cleaner, Battery saver, Blocklist, and many other features will keep your phone fast and secure.
From version 3.9.8:
1. Fixed known bugs.
2. Optimized performance.
