It is estimated that smartphone applications will enable the mobile Health (mHealth) industry to successfully reach out to 500 million of a total 1.4 billion smartphone users globally in 2015 (Jahns 2010).

Not only are consumers taking advantage of smartphones to manage and improve their own health, a significant number (43 %) of mHealth applications are primarily designed for healthcare professionals. These include CME (continued medical education), remote monitoring and healthcare management applications (Jahns 2010).

Kuegler et al. investigated applications using the goniometer function in smartphones, to analyse their availability, reliability and validity versus a universal manual medical-grade goniometer in hand surgery and their applicability in daily clinical practice. They found that 87.5 % (14 out of 16) of the tested applications were comparable to the mechanical goniometer and therefore reliable and valid for measuring angles. They furthermore report that, of the tested applications, no clinical studies related to hand surgery and that so far no Android application was evaluated in a clinical setting (Kuegler et al. 2015).

The available literature supports the use of photography-based and/or computer- and application-aided goniometry, and with today’s technology-keen generation, it could be speculated that it would be easier to find an available smartphone than a standard goniometer in a clinical setting.

The benefit to use a photogoniometer application on a mobile device is the possibility for storing the picture for documentation in medical health records provided there is an institutional agreement on data protection.

It may even be possible that this technology could be used for remote monitoring of patients with Dupuytren Disease in the future.

However, some limitations of photogoniometric measurement should be considered.

Although the small finger is a typical site of the disease, others – mainly the ring finger – are also affected. These fingers are difficult to evaluate with the little finger always being in the way.

The orientation of the camera needs to be standardised: the optical axis of the lens has to be perpendicular to the plane of the moving finger, ideally being the rotation axis of the joint being examined. This might be difficult to achieve, especially when photogoniometric measurements are being performed remotely.