I can usually estimate the time within a few minutes, unless I'm distracted. And just about every room I'm in has at least one clock.

If I need to be somewhere at a certain time, I have a reminder set on Pimlical so my phone buzzes to remind me.

Having a watch on my wrist just doesn't seem necessary, for me, any more.

But, yeah, if your phone doesn't keep accurate time, well, that's a problem. :-)

Cheers,
Scott.