Which accessibility features help visually impaired users most: TTS, captions, or alternate input devices?
All three serve different needs, but their impact varies based on the type of visual impairment.
TTS is the most crucial one. Screen readers like NVDA and VoiceOver rely on TTS to convert on screen content into spoken audio. It’s the primary way visually impaired users navigate apps and websites. But it only works well when the content has proper semantic structure, ARIA labels, alt text, and logical reading order.
Captions are mainly for hearing impairments, though low-vision users who can still read enlarged text may find them useful in certain scenarios.
Alternate input devices like keyboard navigation, braille displays, and voice control are essential since mouse usage depends on seeing a cursor. Any accessible app needs to support keyboard-only navigation at minimum.
TTS and alternate input devices are the clear winners here. But knowing which features matter is the easy part. The hard part is making sure your app actually works with them. A button without a label breaks TTS. A dropdown that only responds to mouse clicks breaks keyboard navigation. A dynamic notification without an ARIA live region goes unnoticed.
This is where testing across real screen readers, browsers, and input methods matters. With TestMu AI, you can validate these checks at scale across real device and browser combinations, catching issues early in your pipeline rather than after users report them.