The Blio eBook apps are very accessible but you can only buy books from the online store if you live in the US, so it's of limited benefit to UK readers at the moment.
Blio was released in 2010 as a Windows application, but with very poor accessibility. More recent updates have added very good accessibilty for PC computers and iOS devices using speech.
Blio for PC
There are keyboard commands built in to the app, and an "accessible mode" which is turned on by default and which makes the menus easier to navigate with the keyboard.
There are no options for font size, shape or colours within a book, and high contrast themes offered by Windows are not supported. The font size for the menus and other windows can be altered slightly through the "Scale" option on the General Settings tab.
Speech users have a better experience. The whole interface, included the library, store and book content screens can be used with a screenreader such as NVDA. Once a book is opened, you can read it either with your own screenreader or with the built-in reader function.
For a more detailed look at the PC app from the perspective of a blind user, download our review of the Blio for PC app (Word, 172KB)
Blio for iOS
The Blio app has six font sizes and 14 font shapes for book content. It also has a boldness setting to make text darker, and text can be fully or left justified. There are three colour settings for text and background.
Blio works with VoiceOver and it's also possible to purchase the Acapela US voices for reading some book content.
For a more detailed look at the iOS app from the perspective of a blind user, download our review of the Blio iOS app (RTF, 57KB)
Blio for Android
Blio has an Android app which has fewer options than the iOS app - four fonts, five font sizes and two colour settings.
Blio works with TalkBack, and it's possible to buy a US English voice to read some books with.