OFeKey Theme SAS PURPLE is a free customization add-on for the OFeKey Pro and OFeKey Free keyboard applications. It allows users to add a custom purple theme to their keyboard. To activate the add-on, users must first download and install either OFeKey Pro or OFeKey Free. They can then download the add-on and select the "Purple Theme" option from the "Available Themes" menu in the app's settings. Once the add-on is activated, users can open their keyboard and see that the theme has been applied.

Overall, OFeKey Theme SAS PURPLE is a simple and easy-to-use add-on for those who want to customize their keyboard with a purple theme. It is compatible with Android 9.0 and is available for free download from the Google Play Store.