I care a great deal about accessibility features, particularly for people with visual impairment. VoiceOver on iOS is a best-in-class screen-reading technology, and Android of course has TalkBack too.
Windows Phone also provides accessibility functionality, which is gathered under the title ease of access.
Text size controls are available, as is zoom, and the ability to make the interface even more high-contrast. Here’s the regular appearance:
And here’s the high-contrast version:
The screen-reader on Windows Phone is called Narrator, and is analogous to the iPhone’s VoiceOver feature.
As on iOS, there’s a quick-launch button combination for Narrator.
Narrator works very much like VoiceOver: putting the device into a mode whereby a single tap simply selects items on screen, reading out information about them, then a double-tap (anywhere) activates the currently-selected item. Even the keyboard interaction works in the same way as iOS with VoiceOver enabled.
There are a few rough edges compared to VoiceOver, like alerts not automatically being read, but it’s still very good. Narrator does currently require US English, but this will presumably change in future.
One small annoyance is that the synthesised voice quality isn’t on par with VoiceOver or TalkBack yet.