Better than iBooks
I have been a loyal Apple/Mac user for 15 years, so its not easy for me to write this, but I have found that many Google Apps are surpassing their Apple counterparts. Such is the case with Google Books. The user experience with its beautiful and cool browsing and reading interfaces are, in my opinion, superior to iBooks. It has great reading/back lighting options and it just seems cleaner overall.
R.A. White about
Google Play Books - Books & Comics, v3.1