DexGuard / iXGuard
visit websiteDexGuard (Android) and iXGuard (iOS) are commercial app security tools that encrypt, obfuscate and self protect mobile applications.
Why do we adopt this technology?
Dexguard and iXGuard add multilayer protection to
Defend against static analysis and reverse engineering
Counter dynamic analysis and tampering with apps at runtime
For a more comprehensive read on why: https://www.guardsquare.com/blog/why-mobile-app-obfuscation-must-go-beyond-name-obfuscation
If you're looking for basic defense against static reverse engineering, you can consider the free and open-source ProGuard.