My neighbor saw me caulking the tub at 11pm and asked why I wasn't using a $3 tool from Ace
I told him I'd been fighting that same gap for 2 hours with my finger and a wet rag, and he just laughed and said 'buddy, they make a little rubber smoothing thing for that,' so now I'm wondering what other basic stuff I've been doing the hard way out of pure stubbornness.
Tossed my finger and rag method out the window about a year ago and never looked back. But the $3 tool thing is a bit off. Caulk smoothing tools come in a pack of like 3 or 4 sizes for a few bucks, and one size never fits every gap. I use the back of a spoon or a plastic putty knife just as often. The real trick is cutting the tube tip at an angle and not overworking the bead.