A Guide to Word Prediction- Call Scotland resource with LOTS of great info about this topic!
Read and Write is speech to text and text to speech with word prediction. All features are free for teachers, 30 day free trail for students, then only basic features like text to speech available for free (list of free features)- available as on-screen keyboard for iOS and Android, as Chrome extension usable on Chromebook, Windows and Mac systems.
EquatIO (from the makers of Read and Write) is a program that allows dictation or prediction of Math/STEM subjects. Has free trial available.
ClaroSpeak (Chrome, Android and iOS) is a text to speech and writing app available for iOS, Android and in the Chrome browser as a Google App, but is also available for Windows 10. It is free and can read PDFs and other documents, but has a synthesized voice. It allows for text customization and has an integrated word prediction program with voice feedback while writing.
WordQ is a word prediction program that is available as iPad app, desktop tool for Windows and Mac ($119/yr), Chrome app (all documents will be saved on Google docs). It provides choices for homonyms with sentence examples and does well with phonetic spelling mistakes. Has exam mode available for Windows / Mac option which allows disabling of some features.
Dyslexia Keyboard iOS $99.99 app, is an alternative keyboard available for iOS that provides word prediction
Clicker Writer $199.99 (in-app purchase to full version), iOS Develop emergent writers' skills and build struggling writers’ confidence with Clicker Sentences - the definitive early writing tool that enables you to build sentences with whole words.
SuperKeys $12.99 iOS Assistive Keyboard gives you just 7 large keys to target instead of over 30 small ones! Just tap the cluster containing the letter you want, and then tap the letter in the enlarged cluster. Has context-sensitive word predictor. The suggestions are displayed on large buttons (you can customize the size), and updates the suggestions as a cluster is opened, making it much more likely that word you want is included. It shows up to 36 of your keyboard shortcuts, which are fully customizable in your iPad's settings to allow you to enter your full name or any other phrase with minimal key strokes.
SoothSayer- Windows word prediction program ($83.40-$149.00 depending on # of licenses purchased)
Google Supports for Reading and Writing (PDF)
FluentType Extension (Chrome) word prediction and auto-complete tool for Chrome, free.
WordBank Extension (Chrome) offers a cloud of core/topic words. Will say the word when hovering over it.
LightKey for Windows, free with optional paid upgrade.
GhotIt Dyslexia keyboard for Windows and iOS (Mac and iPads/Phones) or available as site license. $99-$400 depending on platform and subscription/purchase.