Here is the list of domains app/website wise which needs to be allowed.
1. LinkedIn
1.1 LinkedIn app
www.linkedin.com
1.2 LinkedIn website
www.linkedin.com
linkedin.com
media.licdn.com
2. Whatsapp
2.1 Whatsapp Web
whatsapp.com
whatsapp.net
web.whatsapp.com
crashlogs.whatsapp.net
mmx-ds.cdn.whatsapp.net
2.2 Whatsapp app
g.whatsapp.net
pps.whatsapp.net
mmg.whatsapp.net
3. Twitter website
abs.twimg.com
api.twitter.com
mobile.twitter.com
pbs.twimg.com
twitter.com
4. Reddit
4.1 New Reddit:
www.redditstatic.com
i.redd.it
gateway.reddit.com
v.redd.it
preview.redd.it
b.thumbs.redditmedia.com
www.reddit.com
4.2 Additionally for old Reddit:
www.old.reddit.com
old.reddit.com
5. Skype app
edge.skype.com
api.asm.skype.com
options.skype.com
api.aps.skype.com
people.skype.com
prod.registrar.skype.com
static.asm.skype.com
6. Facebook
graph.facebook.com
connect.facebook.net
pixel.facebook.com
staticxx.facebook.com
b-graph.facebook.com
b-api.facebook.com
mqtt-p4.facebook.com
z-p3-scontent.xx.fbcdn.net
z-p3-api.facebook.com
b-www.facebook.com
z-p3-sonar.fdar1-1.fna.fbcdn.net
If still, a particular function is not working on your phone try adding more domains.
We will be adding more domains for other social apps/sites in the future.