Is it possible to manage filters directly from the Gmail Android app?
This is an old question, but... There is a workaround for managing Gmail filters on your Android device (or any mobile device). You can't do it directly within the app, though. You have to use your mobile browser and go to Gmail's "HTML" website (link below). HTML Gmail is basically a simplified version of the full/desktop website, but it still has nearly all of the functions of the current full site.
Once you navigate to HTML Gmail, you'll see the same options as you would see using a laptop/desktop browser. The graphic interface isn't quite as fancy, but all of the functions are there - including the ability to manage Filters via the Settings tab (near the top right of the page). Then you can proceed with managing your filters as usual.
Here's a direct link to HTML Gmail:
If you have any problems, here's a help article on how to access the HTML Gmail site:
No. This feature isn't implemented in the mobile app.