A lack of rigorous testing of skin cancer detection apps is endangering the public, experts have warned.
The public should be cautious about using the apps until they are adequately regulated, researchers led by the University of Birmingham said.
A review of medical literature found three major failings around some of the apps - a lack of rigorous published trials to show they work and are safe, a lack of input during the app development from specialists to identify which lesions are suspicious and flaws in how the technology analyses photos.
The researchers told the British Association of Dermatologists' annual meeting in Edinburgh that without specialist input, the apps may not recognise rarer or unusual cancers.
And even where the technology is efficient, it may not pick up on all "red flag" symptoms if it has not been combined with specialist input from a dermatologist.
The apps include 'teledermatology', which involves sending an image directly to a dermatologist, picture storage, which can be used by individuals to compare photos monthly to look for changes in a mole, and risk calculation based on colour and pattern recognition.
The researchers found that some of the apps have a comparatively high success rate for the diagnosis of skin cancer, with teledermatology correctly identifying 88% of people with skin cancer and 97% of those with benign lesions.
The team also noted that early diagnosis results in up to 100% five-year survival, compared with 25% in women and 10% in men diagnosed at a later stage.
But they found that colour and pattern recognition software apps seemed to particularly struggle with recognising scaly, crusted, ulcerated areas or melanomas which do not produce pigment, increasing the number of false negatives and delaying treatment.
Maria Charalambides, from the University of Birmingham's College of Medical and Dental Sciences, who conducted the literature review, said: "Future technology will play a huge part in skin cancer diagnosis. However, until adequate validation and regulation of apps is achieved, members of the public should be cautious when using such apps as they come with risk.
"Any software that claims to provide a diagnostic element must be subject to rigorous testing and ongoing monitoring. Apps specifically based on patient education of skin cancer can offer public health benefits in terms of how to stay safe in the sun, or the warning signs to look out for.
"But as per the British Association of Dermatologists' recommendations, most apps cannot currently substitute dermatologist review when it comes to actual diagnosis."
Matthew Gass, of the British Association of Dermatologists, said: "These new technologies for the diagnosis of skin cancer are exciting, but the varying quality available makes it a difficult landscape for people to navigate.
"These apps are not a replacement for an expert dermatologist, but they can be a useful tool in the early detection of skin cancer."
Skin cancer is the most common cancer in the UK and rates have been climbing since the 1960s.
Every year more than 230,000 new cases of non-melanoma skin cancer - the most common type - are diagnosed in the UK.
Approximately 16,000 new cases of melanoma are also diagnosed every year, resulting in around 2,285 UK deaths annually.