Vocalizer TTS Voice English, developed by Code Factory, is an embedded TTS engine that enhances the user experience for GPS navigation, E-Book reading, and assistive software. It offers natural and expressive sounding voices in over 50 languages, which includes over 120 voices. The app provides emoji support, easy customization of pronunciation through a user dictionary, and reading speed and pitch customization. Users can also select number and punctuation reading preferences.

It is essential to note that each voice can be purchased through a simple In-App purchase process. The app comes with a 7-day trial to test voices. However, recent Google apps updates force the use of their own voices. GPS apps (maps) or the AI assistant ignore text-to-speech settings, only allowing Google TTS. This decision from Google has been strongly discouraged by the Android community. As an alternative, Vocalizer voices can be used on other GPS apps compatible with Google Speech APIs, such as "Navigator" or "Sygic." The app is supported on all Android devices from 4.0 onwards.