Whether you're looking for somewhere to have just one more beer, you need a late-night store that sells cough syrup, or you want to do something productive in the early hours of the morning, Wotsopen can tell you which places are open for business near your location.
Wotsopen is free on Android and iOS and is simple to use: Choose Eat, Drink, Shop, Get Cash or Things from the front page to see a list of matching places. The app's other screens let you access a list of places you've previously favourited and search for specific businesses in the area. When you find somewhere you like, you can call the location, open up the business website or get directions to it.
The app taps into data from Google Maps so you're dependent on the opening times information it stores being up to date and accurate, but this is a handy extra tool to have at your disposal -- especially when you're exploring a new place you're not familiar with, late (or early) in the day.