video game controller.
In my youth I was such a wiry square.
Old controllers had wires, and were more squarely shaped (e.g. NES).
Now I've started to select some better friends, and
References to "start" and "select" buttons? "Better friends" may refer to the appearance of more buttons, or better (i.e. more advanced) consoles/games.
I've really taken shape,
Now, controllers are more shapely.
and will live a longer life.
Better batteries and rechargeable packs = longer life.
At least people have always played with me.
They sure have!
I got so much joy, and started to stick
with some nicknames like fatty,
I used to be a real duke!
Previous Xbox controller iterations have been given nicknames "Duke" and "Fatty".