Needing A Bit More Resolution For the iPhone 4

There are couple routes to go with this, the first is to take a look at the Owle Bubo iPhone Camera Kit. It adapts to the front of your iPhone 4 or 4s version and gives one a combo 37mm wide angle and macro capability as well as external microphone in machined aluminum case assembly.
Its possible to go a step further and add the EnCinema 35 adapter kit or buy it together with an Owle Bubo Kit to adapt 35mm lenses to the iPhone 4/4s to give maximum flexibility for depth of field or telephoto capabilities with ones iPhone 4.