> For the complete documentation index, see [llms.txt](https://docs.acecentre.org.uk/products/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.acecentre.org.uk/products/echo/readme.md).
# Introduction
Echo is an AAC app designed for those with a visual difficulty and physical difficulty to access communication.
Echo is based around the concept of auditory scanning. Auditory scanning is a communication method using sound cues or auditory feedback rather than visual cues. This method is especially valuable for those with a visual impairment who cant access visual based AAC.
Echo provides you with two different voices, one for your auditory cues and the another to represent your voice.
## Key Features
* **Auditory Scanning**: Navigate using sound cues instead of visual elements
* **Multiple Access Methods**: Touch, swipe, external switches, game controllers, and facial gestures
* **Facial Gesture Recognition**: Control the app using facial movements for hands-free operation
* **Dual Voice System**: Separate voices for navigation cues and communication output
* **Customizable Interface**: Adapt the app to individual needs and preferences
* **Offline Operation**: Works without internet connection for reliable communication
For a detailed video how to use Echo checkout the video below.
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# Agent Instructions
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