Smartphone apps for weight loss and smoking cessation: Quality ranking of 120 apps.

The tobacco epidemic and burden from overweight/obesity are major causes of health loss in New Zealand.1 Changes to the obesogenic environment and the use of various price signals are probably the most critical interventions required (eg, tobacco tax increases2,3). But there is potentially a place for the promotion of individual-level interventions, including the use of innovative internet and smartphone technologies. In New Zealand, smartphone access has been increasing, and a survey in 2013 found 59% smartphone ownership or access by New Zealand adults.4 It was even higher, at 71%, for those aged 18 to 54 years, and also for Māori or Pacific peoples compared to New Zealand European (70% vs 55% respectively). There is some New Zealand randomised control trial (RCT) evidence for the effectiveness of mobile phone text messaging for smoking cessation,5 with this being equally effective for Māori as non-Māori.6 Work has also been done in New Zealand on smartphone-mediated cardiovascular management7 (eg, as per a New Zealand trial on ‘Text4Heart’8). Internationally, there is evidence detailed in a systematic review that computer-based and other electronic aids can assist with smoking cessation, and are “highly likely to be cost-effective”.9 Another systematic review of five RCTs has reported that mobile phone interventions are effective for smoking cessation.10 But the evidence from RCTs of ‘smartphone apps’ for smoking cessation is fairly limited (eg, we only identified two trials11,12). For smartphone apps for weight loss, one review reported on 10 RCTs which used text messaging or app interventions to support weight loss in women, with significant improvements being observed in eight studies.13 Another review of 17 studies14 that utilised smartphone applications, text messaging and web resources, reported overall weight loss of 0.43 kg (95% CI 0.25– 0.61, p-value≤0.01). But not included in this review were some other smartphone app specific studies which did not report statistically significant weight loss15-18 (albeit some of these being small pilot studies). Given this background of some promising evidence, we aimed to assess the quality of existing apps for weight loss and smoking cessation available for downloading to smartphones by New Zealanders.