As well as the built-in and free options for accessibility software, there are options from commercial organisations. These can cost up to hundreds of pounds, and have more features and offer better training and support.
Paid-for magnification software has high levels of magnification (at least x36), and text can be smoothed at all levels. It also has advanced reading features such as automatic scrolling, and basic text-to-speech built in. It can be used to magnify the log on screen and supports multiple monitors.
There are additional setting to alter the mouse pointer and screen colours. A trial version is available, so you can compare them against each other before deciding which to purchase
Paid for screen readers have a number of features in common. They all support a variety of synthesizers and braille displays, and all have a navigation mode for moving around web pages with single key commands (like "H" for next heading), together with an editing mode for typing information into editable areas.
They all offer verbosity and typing echo options, variable voice speeds, and a keyboard familiarisation mode where you can press a key to be told what it does, as well as a command for reading from the current location to the end of a document or web page. They all have ways to convey information about capital letters or formatting, and settings that can be set per application and invoked automatically.
There is more variation between the products in this category than for the two previous groups.
Magnification ranges from 1.5 up to 50 times with a choice of either full screen and lens modes. It has a full range of enhanced colour modes where you can choose from over 12 text and background colours. It features ClearPoint font smoothing which helps to maintain clear text quality regardless of zoom level.
You can carry your iZoom Screen Magnifier and Reader on a portable thumb drive and use it on any Windows compatible PC without installation. It is available from Pamtrad with prices starting at £250. A free trial is also available to download.
SuperNova Reader Magnifier has all the features of SuperNova Magnifier (see above), and includes speech output for extra support. It comes with a variety of Orpheus, Eloquence, RealSpeak and Vocalizer voices, and a Welsh version of Orpheus is available.
A trial version of SuperNova Reader Magnifier is available, and prices start at £375 from Dolphin.
Dolphin Guide is an all-in-one computer package that has been specifically designed to be easy to use and easy to learn. It presents a simplified interface to commonly-performed functions such as writing letters, sending and receiving emails and web browsing. It also includes features such as a calendar, address book and personal account system.
Dolphin Guide HandsFree is a version of the software that runs with Dragon Naturally Speaking (which has to be bought separately, as does a microphone).
Available from Dolphin from £495. A trial can be downloaded.
Combines ZoomText Magnifier (see above) with speech using NeoSpeech, ViaVoice and TruVoice voices. You can record documents for later listening, or read them in the background while you get on with something else.
ZoomText Magnifier/Reader costs £495 from a number of UK suppliers including RNIB, and a free trial is available to download.
Whereas the other products in this section so far are magnification products with speech support, and are therefore designed for people with some sight, SuperNova Access Suite is a combination of magnification with a full screen reader, including support for Braille displays. It comes with Orpheus, Eloquence and Vocalizer voices.
SuperNova Access Suite is aimed at individuals who have a varying level of sight, and organisations that want to provide a solution for people with a range of visual impairments.
A free trial of SuperNova Access Suite is available, and prices start from £815 from Dolphin.
There is very far less assistive technology software available for Mac OS X than for Windows, partly because far fewer people use Mac computers and partly because the built-in accessibility meets more people's needs. Two products that do exist are:
Visio Voice builds on the existing accessibility built into the Mac OS X by adding additional voices, a document reader that can highlight words as they are spoken, and large cursors. Some of its other features, such as multilingual voices and a lens zoom mode, are available in Mac OS X Lion but not earlier versions.
A trial of Visio Voice are available, and the full version costs 249 euros from AssistiveWare.
ZoomText Mac includes magnification up to x36 with smoothing. It's not the same xFont technology available in the Windows version of ZoomTex, but it's far better than what's on offer with OS X's built in Zoom.
ZoomText Mac also has a number of options for screen colours, mouse pointer and text cursor. It costs £375 from Sight and Sound, and a demo is available.
SimplicITy Envelope software can be installed onto a Windows XP, Vista or 7 computer. It is aimed at people who have never used a computer or are struggling with the complexity of Windows, and may be suitable for someone with mild sight loss. It costs £60 and includes a set of video tutorials.
Ordissimo sell laptops starting at £499 and a tablet for £399. These have their own software based on Linux and Open Office. It is not aimed at blind or partially sighted people, but may be useful for someone with mild sight loss. They come with a simplified keyboard with keys for functions like Copy, Paste and Zoom, so that you don't have to worry about key combinations or finding them on a menu or toolbar.