Onclickads on Android 6.0.1

[Hitar Petar]

I have read a lot of the articles about how to remove the above and tried most of the Apps for adware/malware/junkware removal. I have also Factory Reset my mobile and Router 3 times now, but still no effect.
Every time I do the Reset once I start using either Chrome and Firefox I get the Onclickads which redirects me to something else.

 

[LabZero]

It seems that the problem is related to DNS server ( because of DNS changer malware or similar ).
Here below the original article for router, Windows and Android, you can consider to change DNS on Android firstly or on the router for your entire network.

You can use Google DNS and check if you've solved.

Google DNS : 8.8.8.8 - 8.8.4.4

On Your Router
If you want to change the DNS server for your entire network, you’ll need to do it on your router. All the devices on your network — PCs, smartphones, tablets, game consoles, and anything else connected to the network — get their DNS server from the router. By default, your router uses your Internet service provider’s DNS servers. Change the DNS server on your router and every other device on your network will use the DNS server you specify.

To do this, just access your router’s web interface — how you do this will depend on which router you have. If you’re not sure how to do this, you’ll probably want to glance at your router’s manual to see instructions and learn the default password you’ll need.

Once there, you’ll probably find a DNS option on one of the pages. Change this and the setting will affect your entire network. If you’re having trouble finding the option, search your router’s manual or perform a Google search for your model of router and “change DNS.”

The Ultimate Guide to Changing Your DNS Server