It's not clear from my source how this differs from the LitRes apps for iOS or Android, or the LitRes ebook reader, but I suspect that LitRes is filtering the selection for age-appropriate content.On the other hand, that might not be the case; Barnes & Noble released a similar app in 2010 (NookStudy) which did not restrict the content it could access. Of course, that was intended more for college students so it made sense to avoid restrictions.
LitRes for Schools has the same basic features as the other LitRes apps, including syncing bookmarks and reading location font size, line spacing, margins, and color options; and a night reading mode.
You can find the app in iTunes.
LitRes originally launched in 2006 to provide a legit alternative for pirated ebooks, and it is now reportedly the single largest ebookstore in Russia. This company recently completed a round of financing in which they raised $5 million. LitRes sells around 380,000 Russian language titles from over 100 publishers in print, digital, and audio. The ebooks and audiobooks can be read in LitRes' apps for Android, iPhone, and iPad as well as on LitRes's own branded ebook reader. The LitRes Touch a 6" ereader with a touchscreen, Wifi, 2GB of storage, and a retail price of 2999 rubles, or about $93.