Seconds
I've been browsing iphone blogs for years looking for a solution for the missing clock seconds on the lock screen. Since my iPhone opens with a clock face, I stopped wearing a watch about 3 years ago, which has me check in every now and then to see if Apple has possibly responded to this clock-seconds request. Unfortunately they went in the opposite direction and removed second from the world clock.
Recently I ran across the Zoom feature, which may help some of those who need seconds. It's not an elegant solution and may cause more problems than it's worth for some, but it works great for me. I turn it on when I get in my car in the morning and it gets me to the train station with seconds to spare.
Settings, General, Accessability, Zoom.
It's got a lot of features to experiment with (window, etc.), but I just turned the switch on (I also set it to maximum zoom). When I want to see seconds I double tap the screen with 3 fingers and pan with 3 fingers to the clock icon. The icon is now huge and the second hand is clearly visible. Double tap again to turn it off.
It took me 3 or 4 mornings for my brain to get used to judging the minutes without the tick marks, but it's just like riding a bike...