I am another who dearly wants an apron to work but, I just can't seem to deal with them. I've tried everything from full aprons to just the waist bags. I even modified a belt-clipped tool holder to hold just the items I use when selecting stock and marking parts. This is the only version of wearable tool holder that has survived the 'proof of concept' testing with me.
My alternative to the apron has been my methods and working habits. I have things that I use in a certain area for certain tasks stored in those areas; shallow drawers at the bench for chisels, rules, marking gauges / knives and the like. Tools involved with sharpening tasks are at the sharpening area so I don't have to go looking for them and other such 'work station' like approaches to tool gatherings. This means I have a few tapes, 6" rules and calipers at different places around the shop but, it works for me.
I am just a bit too mobile or too clumsy for the apron. I am constantly catching it on something or trying to move in a way that it resists. I still look at them longingly and hope to stumble on a design that will be useful and still allow me freedom of movement.