The publisher, which has been waiting for three years to launch the e-book store, will continue to expand, starting with one-click buying and an e-book library in 2014. A special student handbook in EPUB 3 format is also in development.

Kovač said the publisher had encountered several problems on its way to opening the store, mainly connected to high costs of e-books, which proved to be as expensive as hardcopy.

This is due to higher value added (e-books are subject to the standard VAT rate, not the reduced rate) and costly copyright, especially when it comes to translations.

The publishing house designed the store in cooperation with the company Impelsys and plans to learn from the mistakes of others in doing business.

In the online store, registered users can search the available titles, authors, keywords and even book contents, which is "revolutionary, because the users can choose a specific term and search all the available books' contents," said Mladinska knjiga online business manager Robert Bolčanšek.

The search engine then shows the number of hits and the books in which the search term appears.

Users can then download the chosen books on their devices or store them in the cloud.