I say go for the SkySafari 5 Pro!
SkySafari 5
SkySafari 5 shows you 119,000 stars, 220 of the best-known star clusters, nebulae, and galaxies in the sky; including all of the Solar System’s major planets and moons, and more than 500 asteroids, comets, and satellites. ($1.49)
SkySafari 5 Plus
SkySafari 5 Plus shows you 2.6 million stars, and 31,000 deep sky objects; including the entire NGC/IC catalog, and 18,000 asteroids, comets, and satellites with updatable orbits. Plus, state of the art mobile telescope control. ($7.49)
SkySafari 5 Pro
SkySafari 5 Pro includes over 27 million stars, 740,000 galaxies down to 18th magnitude, and 620,000 solar system objects; including every comet and asteroid ever discovered. Plus, state of the art mobile telescope control. ($19.99)
(prices as of today and as always, subject to change)
I may start using my smartphone for more than monitoring my tweet stream. 😉