I was sailing in Bora Bora a few years ago during May, at about 16 degrees S latitude. Sun's declination was probably 15 N at that time, so sun was to the N at midday. As someone who's lived in the northern hemisphere my whole life, it seemed strange, and when navigating around the island I realized that I do subconsciously navigate by the sun all the time, as it was throwing me off a bit when things were reversed.

I've used my iPhone's compass a few times when traveling and no sky was visible due to clouds.