Bismillahir Rahmanir Rahim.

Assalamu 'alaikum wa rahmatullahi wa barakatuh.

You can bookmark any page or even a specific ayah on the page. Only one bookmark can be placed per page. 

To bookmark a page

Simply tap the ribbon indicated by the arrow to bookmark the page.

Page bookmarked.

To bookmark an ayah

Tap and hold the ayah you want to bookmark and an option menu will appear. Tap the Bookmark Ayah option as indicated to bookmark an ayah. 

Ayah Bookmarked

To go saved bookmarks 

Tap anywhere on screen and the bottom menu will appear 

Tap the bookmark option in the bottom menu as highlighted below

Tap any saved bookmarks to go to that page. 

JazakAllah Khair