I have two signed Android APKs that share the same brand: a Chinese-language build that already handles user registration smoothly, and an English-language build that currently lacks this flow. My goal is to extract every user-management API call from the Chinese APK—endpoints, headers, payload structures, encryption or signing logic—and transplant that functionality into the English APK so both variants register users in exactly the same way. What I can provide: • The release APKs for both language versions • Valid test accounts and server access for live registration checks • Any additional assets the Chinese build relies on (native libraries, certificates, config files) What I need from you: • Decompile, inspect and document the Chinese APK (jadx, apktool, Ghidra or your preferred stack) • Identify all code paths involved in user sign-up, token generation and profile creation • Recreate or patch those calls into the English APK’s codebase, preserving obfuscation or security routines where necessary • Supply a clear mapping sheet (URL, method, headers, crypto steps) and a small proof-of-concept build of the English APK that can register a fresh account successfully on our production server • Short write-up on how to repeat the process for future releases I’m ready to sign an NDA and provide immediate access to the binaries. If you have deep experience unpacking, tracing and re-implementing Android network traffic, you’ll find everything else straightforward; just let me know which tooling you prefer and how long you’ll need once you see the APKs.