Perhaps the best place in India for a proper old-fashioned night out on the tiles, Mumbai has plenty of choice, and offers great value entertainment for revellers wanting to enjoy themselves. Prices start at around £1 for a beer in one of the smaller local pubs, although in hotel bars, and the pleasant wine bars along Marine drive, prices roughly double.
You should really dress according to the kind of place you're going to, and be aware that many nightclubs have a couples only policy as well as closing comparatively early.