Android
Information regarding Android accessibility features can be found at:
Google Support: https://support.google.com/accessibility/android/answer/6006564?hl=en
Computer World: https://www.computerworld.com/article/3346010/android-accessibility-features.html
Verizon: https://www.verizonwireless.com/support/knowledge-base-215346/
Android Authority: https://www.androidauthority.com/best-disabled-apps-and-accessibility-apps-for-android-586626/