I'm on Android 6 on a Nexus 5, though I had this problem when I had Android 5 too.
For some reason, items I sync with Dropbox aren't immediately propagating to my Android device, even after I force a refresh. I haven't seen anything missing on Windows. I've tried reinstalling / clearing data, but the problem always comes back. I just checked and I was able to send a delete from Android to my Mac without trouble. Any ideas or known issues?
1Password Version: 4.5.3b1
Extension Version: Not Provided
OS Version: Not Provided
Sync Type: Not Provided