Hello guys, I have a question with regards to spying , I have read IAmAttilia's ultimate spying guide for media buy, But what if i am looking to spy on mobile pops?
Is there actually anyway to spy them manually? (apart from visiting porn sites)
Because often times we won't know which are the targets that our pops will be showing on the traffic source right?
looking forward to some tips ! 
Search on google for keywords like free apk, download apk, from your phone and browse these websites manually via VPN from your desired country.You will see a bunch of pops, sometimes you can also figure out from which traffic source the pop up is.
Save all the websites url in an excel file and next time when you want to spy, you know where to go.
Hope that helps,
Cheers
If you're just sick of visiting porn sites visit a bunch of movie streaming websites, plenty of pops to be found on them too.
What denisoi said! It's very important to do the search and spying from your mobile phone, or better mobile phones of various types (at least one android and apple). Good luck!
Would using a device emulator like User-Agent Switcher to browse as a mobile device via VPN work for spying mobile pops and landers?