This app is not suitable for bengali epub or mobi. Most of custom bengali fonts (which fonts give us- printed book like feel) example- Kalpurush, Solaimanlipi, Adorsholipi Doesn't support here & can't render bengali perfectly. It's take too much time to open Bengali epub. Many other app (Moon Reader, Liberia PRO) which are almost free or Cheap, can manage bengali e-book perfectly more than expected. I don't recommend you to purchase it if you want to read bengali through this app.