The iBooks app on iPhone and iPad not only stores your ebooks but also let you allow to bookmark pages within books for future references. Through guide below you learn how you can create bookmarks for a book in iBooks on iPhone and iPad.
Create Bookmarks within a Book in iBooks
Tap on iBooks app icon from the Springboard of your iPhone or iPad
Open a book, go through the page to which you want to bookmark and then tap on bookmark icon that appears in the right upper corner of screen and it will become red which means page is bookmarked now
Access Bookmarked Pages within a Book in iBooks
Launch iBooks app from the Springboard of your iPhone or iPad and then open your required book
Tap the “Contents” icon
Select “BOOKMARKS” tab, and there you will find all bookmarked pages of selected book, so just tap on any to which you want to open