David Livshin is a professional photographer, but for quick shots, he uses his iPhone more and more.
"I find the opportunity to be unobtrusive sort of wins out over having to lug the cameras around," said David Livshin.
But the iPhone camera, like most smart phones, does not have an optical zoom.
"Smart phones only have a digital zoom that loses pixels as it zooms in; that reduces image quality," explains Terry Sullivan from Consumer Reports.
Consumer Reports tested two new brands of add-on lenses for smart phones.
The Olloclip costs $70 and is a three-in-one lens for the iPhone 4 and 4S.
"You fit each of them over the iPhone's lens," said Sullivan.
Consumer Reports also tested add-on lenses from Photojojo that work with both iPhones and several Android phones.
The lenses cost about $20 each. To use them, you attach a ring on your phone with adhesive. The lenses attach to the ring magnetically.
"We found the ring sometimes came off the phone when we removed a lens," said Sullivan.
And Consumer Reports found a drawback with both brands; the lenses cover the phones' flash.
But in good light, testers found both the Olloclip and the Photojojo lenses can take some beautiful pictures.
"The close-up shots and video of flowers in particular were stunning," Sullivan said.
The upshot, Consumer Reports says these lenses can definitely expand a smart-phone camera's capability.
Be aware the Photojojo only works on phones where the lens is flush with the phone. If the camera lens protrudes, the add-on lens won't attach properly.