The Tattoo lady essentially is a precog almost like Angela. Almost as Angela has to sleep and have interpretive dreams.

When Samuel applies the tattoo ink while she closes her eyes it is like paint of Painter precogs showing illustrative images.

Of course this assuming that the Tattoo lady's power is a precog not one similar to Molly Walker. But as far as we know Molly Walker's power does not cross with time travelling. Precog Painters does as Isaac Mendez was able to follow Hiro's journey through time.

My theory: It's more of a combination of Molly's power and and that history power Angela fed Sylar, Clairsentience or whatever. She can locate a person and instantly knows everything about them/where they've been/etc.