Is truth really stranger than fiction? Sometimes. In today's world, "an app for that" probably exists even if it shouldn't. So it's getting harder to tell whether an app idea is real or fake. In honor of April Fools' Day, we've put together a list of real and fake apps for various mobile platforms. Can you tell which of them are actually available for installation, and which are just figments of our editors' imaginations? Let the guessing begin.