Getting your pals into costumes and out of their apartments on Halloween is hard enough without the added trouble of planning a fun night. Everyone wants to have a memorable night filled with either fun bar crawls, costume contests and . . . maybe even some trick-or-treating. Whatever you choose to do this Halloween — go all out, party hard and best of all . . . save a few bucks on those happy hour appetizers. The following apps ahead will come in handy for picking out all your spooky festivities, so you can spend less time Googling and have more time to boogie the night away with Dracula.