and a wrist watch. I did just fine....
There was a growing habit a little while ago amongst the young not to wear a watch, instead relying on the (then new) smartphone for the time.
I joined a student for a navex and noticed the lack of timing device. He showed me his phone with the time on it, then tucked it under his thigh while we took off and set course. At the first waypoint, I asked him to note down the time, he whipped out his phone which of course had turned itself off. I lent him my watch. When we landed, I said you're not flying again without a watch. He spent less than £10 and got a fine timepiece, which I suspect he only wore for flying...
TOO
ps I've yet to find a C150 or PA28 with a working clock. Fortunately, the ANO allows the substitution of a personal timepiece.