There are plenty of innovative magicians who have turned their phones from pocket-sized computers into magic tricks. One of the latest efforts to make the impossible happen with a phone is a trick called Starlight from Paul Harris and Chris Perrotta. Harris, in case you didn’t know, is pretty smart about the whole magic thing.
When Starlight goes into action, the beam of light from a phone will reveal two symbols on a playing card, so potentially two letters (say, a viewer’s initials) or a number and a symbol (such as to reveal the card chosen by an audience member).
Magicorthodoxy has a review of the product, and he’s generally into the gimmick. Starlight gets brownie points for being well made and easy to use, but he did express concerns about the device being a bit fragile.
If you’re excited by what Starlight has to offer for your act, you can pick it up from Murphy’s Magic.