All this talk of day bags has made me wonder...what does everyone carry around during the day when touring towns or cities? Not hiking or camping (where you may need to carry multiple meals and special gear), or moving between places where you need to have your entire suitcase with you. Just day-to-day touring when your suitcase with clothes and such is back in the hotel - what is in your day bag or purse with you?
I am of the opinion that I don't want to carry too much with me and go fairly light. But I want to have what I consider essentials. One could go lighter, or bagless (easier for those who wear men's clothes with the bigger pockets). However, other people seem to carry everything with them.
What's in my bag on an average day : DSLR camera and attached lens (no extra lenses), phone and small portable charger, money/credit card and ID, small bag with personal items (a few advil, tums, band aids, chapstick or lipstick, tissues, sunscreen), sunglasses, and earbuds. I may wear a jacket, scarf, or sweater at the beginning of the day and end up carrying it if it gets warmer.
Before my iphone I would have a map and guidebook, but those are now on the phone.
So - do you fall into the "be prepared and take everything you may need" camp or the "I'll be fine with 50 euros and my ID" camp?