Smart phone apps can help you check your vision, keep tabs on your blood-glucose levels and track your blood pressure. Earlier this year the U.S. Food and Drug Administration even approved an app that allows doctors to view scans on an iPhone or iPad to help them make diagnoses on the go. But fancy apps aside, the cameras on these devices and others can help health care workers in remote or understaffed areas submit photos of complicated conditions to doctors who can verify or make a diagnosis.

One question that quickly surfaces is whether cell phone cameras are good enough to transmit microscopic information to experts. A new study found that many simple bar phones with cameras could snap a good enough picture through a standard microscope to allow a remote assessment of a sample. The results were published online Wednesday in PLoS ONE.

"Poor and vulnerable populations are most affected by weak laboratory services because they carry the largest burden of ill health," noted the researchers behind the study, which was led by Coosje Tuijn, of the Royal Tropical Institute of Biomedical Research in Amsterdam. And although microscopy is often pivotal in diagnosing common diseases, such as malaria, tuberculosis and other bacterial or parasitic diseases, in poor areas, "microscopy services are often suboptimal," the researchers noted. And "as a result, many common diseases are misdiagnosed and improperly treated, " which can affect patients—and cost the health system time and money.

In Uganda, where there are only eight physicians for every 100,000 people, getting a definitive diagnosis can be difficult. The research team enlisted local health workers to try using their own (or borrowed) cell phones to capture photos and videos of microscopic images to send off for remote diagnosis.

The best images were obtained with cameras that were two megapixels or higher, which are common in smart phones and are in some slimmer Nokia, Samsung and Sony bar phones. And some of the most successful diagnoses were those of samples that contained malaria parasites, which "were often so clear that specific stages of the malaria parasite could be identified"—thus improving targeted treatment. TB was a little more challenging (owing to the small size of its bacteria) and required a fluorescent microscopy and a five-megapixel camera. But phones with video could also grab clips that revealed some other microbes as they moved around, helping to improve the remote diagnosis.

Once the pictures were snapped, health workers could send them directly to a website that could make them accessible to experts for diagnosis and/or students for training. Direct feedback, via phone call or text, could then be sent to the user's phone.

Innovations to use cell phones to help read microscopic images have been around for years. One version, CellScope, uses a Nokia bar phone, LEDs and an adapter to function as a microscope and was described in a 2009 PLoS ONE study. Another type also uses LEDs but takes advantage of biological cells' transparency to discern patterns in the sample's shadows.

"Connecting mobile technology to diagnosis has a considerable potential to improve diagnostic services in resource poor settings with widely distributed and remote clinical centers," the researchers behind the new paper noted. So far, the team found that the biggest stumbling block was simply getting the cell phone attached to the microscope connector—an obstacle that the researchers are already working to solve.