Traditional book publishers are catching up on the e-book trend by launching their first joint sales and reading platform this summer. Sino United Publishing, which comprises the city's biggest book publisher-retailers - including Commercial Press, Joint Publishing and Chung Hwa Book - plans to launch Super Book City later this month. About 1,000 new e-books will be available on the platform, general manager Terence Leung Wing-chung said. "New e-books will be 20 to 30 per cent cheaper than their printed counterparts," he said. "Older ones may be 60 per cent cheaper than printed versions." The first batch of e-books to be offered will be in Chinese, covering various categories such as general knowledge, encyclopedias and works by celebrities. Leung said publishers had produced e-books before, but never so many titles. It was also difficult for readers to find the books without a common sales platform. "The development of e-books in Hong Kong is much slower than in Europe or the United States. By launching the new platform, we would like to speed up the pace," he said. The platform will be available in various formats to fit personal computers and mobile gadgets. Users of mobile phones and tablets - running either Apple's iOS or Android - can download an application in the App Store or Google Play, respectively, which will allow them to purchase and read the e-books. The app is still being evaluated by Apple, but the publishers hope it will be available from July 17, the day the annual Book Fair opens at the Convention and Exhibition Centre. The superbookcity.com website will be launched on the same day for desktop computer users. Initially, however, buyers will only be able to open and read their e-books on mobile devices, after they have downloaded the app - not via the website. Apart from buying e-books, shoppers can also buy printed books on the e-platform. A million books are included in the catalogue. They can either have the books delivered to their homes with a postal fee, or collect them in person at bookstores with no surcharge. In coming years, the group would like to increase their collection of printed English books on the e-platform to about a million. It has set no target for the number of English e-books to be offered.