POP3 is your problem. If you setup a spam filter at the server using the webmail interface, it filters it there ok. You check your webmail and spam is in the spam folder, like it's supposed to be. But POP3 is not capable of syncing folders to your phone or other computers. All email is still sent, unfiltered, to your phone an shows up in the Inbox, as you found out. You need IMAP email to sync folders.
You have 3 ways to deal with this:
1. See if you can convert the POP3 service to IMAP. This is the best solution and I highly recommend it if possible.
2. Next best is to forward your POP3 account to Gmail for handling. Not a perfect solution, but this will give you most of the the advantages of IMAP service with your POP3 account.
Some of the advantages of IMAP are:
Filtering and sorting into folders can be setup and done on the server and everything syncs to all your devices and computers.
Setup of filters and sorting only has to be done one time instead of repeating it on every device and computer.
All email is kept on the server so you download only as much email as you need to your phone, but all email is available if you need it.
You can get Push notification of new email.
3. Last choice. There is only one Android email client I'm aware of that can do sorting of POP3 email on the device, like a desktop email client does, by defining filters (aka rules) by email address, keywords, etc. That is Maildroid.
https://forums.androidcentral.com/e...details?id=com.maildroid&hl=en&token=tO2zmoNJ
No other clients I've seen support on-device filtering. This is because it's space, data and system-intensive to do it on your phone.
Since you would still be using POP3 service...
It does not sync from the phone to other devices or computers.
You will not be able to get push notifications.
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