Friends, my friends, tag filtering is now NATIVE to tumblr. You can use it on mobile. You can use it on desktop. It doesn’t really work if you follow people who don’t tag, but Pearl is excellent at tagging. That’s one reason tagging posts is important! And now you can stop sending passive-aggressive anon messages to make the good-at-tagging recipient feel guilty when you clearly have an account and can help yourself out.
Go to settings. On mobile, under Global settings > Filtering and then add whatever it is you want to filter. On desktop, filtering is in Account Settings. Add whatever it is you want to filter. It carries over from desktop to mobile and everything.