Latex based interior paints take between 14-30 days to fully cure, 1 hour to be dry to the touch and around 4 hours to recoat. Latex based exterior paints take around 14-30 days to fully cure, 2 hours to be dry to the touch, and around 4 hours to recoat. 

For bathrooms, ideally wait 14 full days before using the shower/tub after painting it; if that is not feasible, at least wait a minimum of 48-72 hours. The longer you wait, the better the paint will hold up. The goal should be to minimize wall exposure to moisture while the paint cures on the wall. Taking baths instead of showers, or quicker showers, with less hot water, and keeping the fan on while showering and afterwards, also helps.