Great for use in any play! This is my go-to lube for almost anything.
I find that it is most effective in the shower, or where things are going to be very wet, regardless of lube. It does tend to wash away faster with warm-to-hot water though.
I have found that it does tend to seep out of the edges of the cap, so you may want to store this in a sandwich bag to keep your toy area clean.
Do not use with silicone toys! Reactions can occur between the lube and the toy that likely will cause the toy to melt.
I also like to use this for shaving, it reduces razor burn and leaves the skin very soft after.