It is estimated that by next year, 500 million smartphone users worldwide will be using a health app.
According to the Food and Drug Administration (FDA), mobile health apps are "medical devices that are mobile apps, meet the definition of a medical device and are an accessory to a regulated medical device or transform a mobile platform into a regulated medical device."
There are apps that allow us to monitor almost every factor that impacts health, including weight, exercise, blood pressure, cholesterol levels, sugar levels, heart rate and sleep quality, and some can even detect cancer.
And the list continues to grow. Earlier this year, Medical News Today reported on two studies detailing the creation of new smartphone apps that developers say can detect epilepsy and improve the care of stroke patients. A more recent study revealed that researchers from the University of Washington are developing a smartphone app that they say allows parents to screen their newborns for jaundice.
An abundance of personal health data is quite literally in the palm of our hands. But not surprisingly, the effectiveness of these apps has been questioned.
Do calorie-counting and fitness apps pull their weight?
Last year, the IMS Institute for Healthcare Informatics conducted an analysis of more than 40,000 health care apps available for download on the US Apple iTunes app store, looking specifically at how these apps benefit consumer health.
Only 16,275 of these apps are directly linked to patient care and treatment, according to the investigators, while the others provide information that in no way improves patient health or well-being.
The most downloaded health apps are those that claim to help with dieting, weight loss and fitness.
The most downloaded health apps are those that claim to help with dieting, weight loss and fitness. Some of the most common include MyFitnessPal and FitBit - free calorie counters and fitness trackers.
Last year, MyFitnessPal pulled in 40 million users, but the report from the IMS institute claims that its effectiveness did not meet its popularity. In fact, they point out that very few studies show that calorie-counting apps are effective.
Similar findings were echoed in a study by researchers from the University of Massachusetts Medical School, in which they compared 30 popular weight-loss apps with traditional weight-loss strategies.
The team found 25% or fewer lifestyle-based strategies for weight loss - such as portion control and identifying reasons behind overeating - were incorporated in 28 of the apps, meaning they were likely to be ineffective for weight loss.
"Our results indicate that many app developers are not including proven behavioral strategies in their apps," said study author Dr. Lenard Lesser. "Without long-term data on whether these apps work, it is hard to recommend them as the solution for poor eating habits. While we await that data, app developers should work with health professionals to make sure they are making their apps as beneficial as possible."
But not all research condemns the effectiveness of weight loss apps. In 2012, a study from Northwestern University in Evanston, IL, claimed an app that tracked eating and physical activity helped users lose 15 pounds and keep the weight off for at least a year.
The team admitted, however, that the app was only effective when used in conjunction with other weight loss support, such as nutrition and exercise classes.
Could health apps be detrimental to health?
Ineffective weight loss apps are one thing, but some health care professionals say the effectiveness of other health apps could mean the difference between life and death.
Using photos of 188 skin lesions - 60 diagnosed as melanoma and 128 diagnosed as benign - the researchers tested three apps that use algorithms to determine the likelihood of cancer, while the fourth sends images of skin lesions to a dermatologist for assessment.
The team found that even the most accurate of the apps that used algorithms missed 18 of the 60 lesions diagnosed as melanoma and deemed them low-risk for cancer.
Commenting on these findings, Dr. Darrell Rigel, of the NYU Langone Medical Center in New York, NY, told ABC News:
"It is very concerning that these apps are used for diagnosis by patients, as it could lead to delay in diagnosis of melanoma, the cancer which is perhaps the most critical in early diagnosis being important for survival."
The researchers pointed out that the developers of these apps had stated that they are designed for educational purposes rather than cancer diagnosis and should not take the place of standard medical care. But the team said their findings are still worrying:
"Releasing a tool to the public requires some thought as to how it could be misused. This potential is of particular concern in times of economic hardship, when uninsured and even insured patients, deterred by the cost of co-payments for medical visits, may turn to these applications as alternatives to physician evaluation."
No need for medical input when developing health app
You do not need to be a medical professional or source medical input to develop a health app, and some experts say this poses problems.
In a report for the American Academy of Orthopedic Surgeons, Dr. Orrin I. Franko, of the Department of Orthopedics at the University of California-San Diego, explains:
"The approval process generally requires that the app meets each company's guidelines and pertain to content matter, but the process does not validate the data contained within the program for medical accuracy or functionality before making the app available for public use."
"The result is an easily accessible library of mobile health applications without validation or peer review that can be downloaded by patients, students, and providers alike.
Although some apps include a legal statement, they are not required to disclose their limitations or information sources. As a result, a legitimate concern regarding the development of harmful apps exists."
Last year, the FDA issued final guidance for developers of mobile medical apps. The organization stated that they will focus on regulating a small number of medical apps that they deem high-risk for consumers, such as mobile apps that are intended to be used as an accessory to a regulated medical device, and those that transform a mobile platform into a regulated medical device.
They noted, however, that because many mobile health apps do not meet the definition of medical devices under the US Federal Food, Drug and Cosmetic Act, it does not regulate them.
Although the FDA guidelines are a step forward in ensuring the safety and effectiveness of mobile health apps for consumers, Dr. Franko said more needs to be done:
"Clearly, greater involvement of true health care professionals in the creation, development, and review of apps is a crucial step toward ensuring the safety of patients and reducing the risks of providers."
Sharing data with doctors
Although the effectiveness of health apps has been questioned by some, many believe the apps are transforming the medical world for both patients and health care providers.
As well as just monitoring our health, many apps can be a portal to better health care by boosting communication between doctor and patient.
One of the most recent examples of this is the Apple HealthKit - finally released yesterday after 2 weeks of software problems.
For the individual who uses the app on their iPhone or iPad, the tool will provide an "easy-to-read dashboard of your health and fitness data." Basically, it pulls together an array of information that is collected by third party health apps and displays them in one place.
But what is most innovative is that you can choose to send your health data to your doctor. "For example, you can allow the data from your blood pressure app to be automatically shared with your doctor," Apple explain on their website.
Back in June, Google announced they will be launching a similar platform, called Google Fit. A launch date is yet to be confirmed.
Apple HealthKit - not necessarily 'the beginning of a health revolution'
According to Apple, HealthKit "just might be the beginning of a health revolution." But some medical professionals are not so sure.
Once again, the issue of accuracy is raised. Speaking to Forbes, Dr. Dushan Gunasekera, a medical graduate of St. Bartholomew's Hospital in the UK, says:
This month, Apple launched HealthKit - a platform that brings all your health data together in one place and allows you to share it with health care providers.
Image credit: Apple
"Whilst having this data could be of use, a doctor is unable to guarantee that whichever blood pressure monitor, glucose monitor or fitness tracker a patient is using will be accurate. Because of this, it's unlikely that we'll ever be at a point where a doctor will take a look at your phone and be able to give a diagnosis."
Dr. Gunasekera adds that HealthKit could also affect users' mentality and make them paranoid about their health.
"The key to Apple HealthKit being useful all rests on the data produced being interpreted correctly," he says. "There is certainly a risk that people will see a sharp dip in one of their graphs and interpret that as a big problem, when in fact the reading could still fall within a normal range."
And of course, there is the issue of data protection. Apple ran into some trouble recently when it emerged that hackers had accessed nude photos from celebrities' iCloud accounts - Apple's online storage system. This raises the question: will users' HealthKit data be safe?
MNT put this question to Apple, but we have yet to receive a response.
Apple have already warned developers using HealthKit to ensure users' data is kept away from iCloud, and have stated that data cannot be sold to marketers or other businesses that may sell it on. With permission, however, it can be sold for research purposes.
Despite concerns, Dr. Gunasekera notes that HealthKit does have numerous benefits. For example, he told Forbes that diabetics could benefit greatly from the app:
"Diabetics have to constantly measure their blood glucose level, which is traditionally done using a pinprick and a small amount of blood being analyzed with a portable device. But there are tiny monitors that can be implanted under the skin that can track blood glucose that could then be tracked using something like Apple HealthKit."
He says it could also be very useful for expectant mothers, as they need to ensure their health is closely monitored during pregnancy.
"Monitoring something like heart rate would give mothers a way of ensuring their baby is doing well. There are ways to do this at the moment, but it involves regular prenatal checkups and there's no real way of tracking stats in-between. By wearing a monitor at all times a mother could have her iPhone alert her if something was amiss."
The use of HealthKit in clinical trials
But it seems Apple are using HealthKit to take their "health revolution" much further than just doctor and patient.
It was recently announced that the platform is being used in two separate clinical trials. One trial involving researchers from Stanford University Hospital, CA, is using HealthKit to allow doctors to track blood sugar levels in children with diabetes.
The other trial - involving researchers from Duke University in Durham, NC - is using HealthKit to track blood pressure, weight and other health measurements in patients with heart disease or cancer.
Commenting on the integration of HealthKit into clinical research at Duke, Dr. Ricky Bloomfield, director of mobile technology strategy at the university, says:
"HealthKit will provide patients the option to seamlessly share their own health information with their physicians. This technology has the potential to advance the utility of electronic medical record systems and to simplify the ability for patients to share information with their providers."
Until there is solid research confirming the accuracy of all health apps on the market, their effectiveness will continue to be questioned.
It seems, however, that with downloads of health care apps set to boom in the coming year, consumers, health care providers and researchers alike are positive about what they can do for the medical world.
Writing in a guest post for Forbes, Derek Newell, CEO of Jiff - a social network and apps platform for health care - says:
"In the future, everything that can be done digitally will be done digitally. Digital health apps will schedule appointments, tell you the doctor is running late, help monitor medications' side effects, and help you follow your care plan accurately. These changes will engage patients with their health and health care in new ways. It will also radically reform health care delivery."