Since Codex is an APK file and not hosted on the Google Play Store, you’ll need to allow your phone to install it: Go to > Security (or Privacy). Toggle on Install Apps from Unknown Sources . Step 3: Install the APK
Locate the downloaded file in your "Downloads" folder and tap it to begin the installation. Once finished, you’ll see the Codex icon on your home screen. The Codex Key System: How to Get Started codex executor download latest version