When BlackBerry 6 OS finally dropped, I rejoiced at one of the new features: threaded messages. Years of Gmail use made threaded messages feel so natural. Instead of a new listing for each reply, Gmail groups emails and their reply threads in one listing, which makes life a lot less cluttered. BlackBerry 6 brought this innovation to our favorite smartphone in 2010, and it made an already great email system even better. Did you know that you can easily navigate through threaded messages with just a couple of keystrokes, though? Once you’ve opened an email in a threaded message, you can hit J or K to navigate. Pressing J brings you to the next oldest message, while pressing K brings you to the next newest message. So if you’re on the most recent message in the thread, K won’t do anything, but J will bring you to the second-newest message. In the same way, if you’re on the oldest message in the thread, J won’t do anything, but K will bring you to the second message in the thread. Since discovering this I’ve used it constantly to flip through messages in a given thread. It’s much easier than backing out and selecting the next or previous message. It’s even easier than backing out and selecting a different message in the thread. In other words, it’s efficient. Aren’t we BlackBerry users all about efficiency?