Nexus 5-Facebook and Whats app issues

[AC Question]

Hi, I am using Nexus 5 and i am facing below issues while using Facebook and Whats app .

1)Facebook:While using FB, and checking News feeds, if i get any other notification lets say whats app message, and if i check that msg and again cm back to FB then my news feeds is auto refreshed . This is very hectic because while using FB and checking news feeds u go down on various posts and if it get auto refreshed then it sucks.

This issues is also there while reading any post, if u click read more and after reading u cm back to the post bt it is auto refreshed.
This issues is also there while using share>Write post.

2)Whats app: open whats app>go to contacts > and scroll down for 2-3 pages(10-20 contacts). click on any contact and press back button. Normally same contact should be displayed. But For Nexus 5, list again starts from TOP.
This is really bad defect.

Please giv me suggestion.

Thanks,
Sagar.
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