Gunners

You can choose to automatically hide threads that you've read. I think that's a native feature, but I know many/most of the native clients support it.

If you're checking often enough that you're seeing the pinned threads that often you can also change your sorting. Anything with a time restriction won't show pinned threads that fall outside that window. I often use top ____ when browsing all specifically to avoid the meta posts that can be pinned for weeks.