The free app only gives you access by copy and pasting texts. You don’t need an account to access the free app, therefore your progress will not be saved.
You can access the free app here: http://www.spreeder.com/app.php
While Spreeder CX is the premium version where you are required to create an account thus progress is saved and synced across different devices. It has advanced importation feature that allows users to upload PDF, Word, HTML, TXT, ePub files, has 20,000+ pre-built free e-books, and speed reading course.