This study descriptively explored user preferences for an app designed to improve intake of bioavailable iron in premenopausal women. Participants were provided with a link to download the mobile phone app and were asked to use the app at their leisure over at least a 2-week period, during which time they were asked to read information, play games, set goals, and take photos of meals. Continued use of the app was encouraged via a reminder email sent to each participant during the trial period. Following this 2-week period, semistructured focus group discussions were conducted to determine users’ opinions of the app.

The content of the Women’s Iron, Zinc, and Energy (WIZE) app was developed based on a systematic review of the literature on dietary factors influencing iron status in combination with findings from 2 dietary intervention studies investigating dietary strategies to increase iron status in women [11,20-22]. In addition to providing information on rich sources of dietary iron, the app also included recommendations to increase iron-fortified food intake, consume foods rich in vitamin C with meals, and avoid consumption of tea and coffee with meals, based on previous studies highlighting efficacy [11,20-23]. The app incorporated successful strategies of behavior change such as those found in social cognitive theory [24], the health belief model [25], and self-determination theory [26]. Strategies for behavior change that were utilized by the app included goal setting, monitoring, feedback, self-motivation, and strategies for knowledge acquisition.

The app delivered iron-related nutrition information in 7 fact sheets, which were designed to increase knowledge of dietary sources of iron and the relationship between iron and health. In addition to increasing participant knowledge about iron, it was hoped that informing users about the detrimental health effects of low iron levels would help to make iron status personally important to users. It is theorized that this would promote self-motivation within users and further encourage behavior change.

The use of games has previously been shown to encourage knowledge uptake; therefore, games (word search and word jumble) were included to develop further iron-related knowledge and facilitate participant engagement and use of the app [27,28]. One goal per week was established (eat 2 iron-fortified products each day, eat 50 mg of vitamin C with meals, aim to eat 12 points of iron each day, and drink coffee and tea at times other than during meals), which aimed to increase iron intake and absorption through gradual implementation of dietary change. To assist women in meeting these goals, a goal tracker was included to record adherence and to monitor participant progress toward each of the goals. The photo diary function was included to help participants monitor and review their food intake if they found they were not meeting specific goals. Screenshots of the app are shown in Figures 1-3.

As it is intended that this app be widely available to all premenopausal women interested in increasing intake of bioavailable iron, the current study was open to all women between the ages of 18 and 50 years, irrespective of iron status. However, to use the app, participants were required to have access to an Android mobile phone and be able to communicate in English. Participants were recruited via convenience sampling through flyers placed around Deakin University, Melbourne Burwood Campus, Australia; supermarkets in the surrounding area; free advertisements placed on Facebook pages and Deakin University Student Association club websites; and via presentations given before lectures. All participants filled in a brief background questionnaire collecting information about their age, highest level of education achieved, current degree and major (if studying), current app use (How often do you use apps? What kind of apps do you use? Would you pay for an app?), and current employment status. Ethics approval was granted from Deakin University, Australia and all participants provided written informed consent.

After using the app for at least 2 weeks, each participant attended 1 focus group discussion lasting no longer than an hour, and consisting of 6-7 participants per group. Focus group discussions were conducted by 2 researchers with one leading the discussion and the second recording field notes. Verbal data from the focus groups were collected through audio recordings. During the focus group discussion, participants were asked about their likes and dislikes, and reasons for each, for each section of the app. They were also asked about their opinions on the look and feel of the app, content and ease of use, and any suggestions they had to improve the app.

Data collection continued until saturation occurred, which was when no new themes or ideas were emerging from the data [29]. The same researcher (DM) led each focus group.

To help ensure research quality and rigor, approaches highlighted by Braun and Clarke [30] and Fade [31] were employed throughout the study. Audio recordings of the focus groups were transcribed verbatim and anonymized, and a thematic analysis was undertaken [30]. NVivo 10 (QSR International) qualitative research software was used to help manage data and aid analysis [32]. Following familiarization with the data, initial codes were generated in a systematic fashion. Data were collected relevant to each code and themes were then identified and reviewed [30]. An inductive open-coding method was utilized [30]. Codes generated included usability, technological errors, games, facts, and goal tracker. Responses could be coded to more than 1 theme; for example, to both the usability and games themes. Frequencies of code occurrence were then calculated. Samples of analyzed sections of the data were double checked by a second researcher (AOB) to help eliminate bias and ensure accuracy.

Twenty-six participants attended the focus group discussions. The age range of participants was 18-36 years (mean 24.7, SD 5.2). Participants’ iron levels and whether they were pregnant or breastfeeding were unknown. All quotes are presented in intelligent verbatim.

Two themes (Table 1) were identified from the focus groups with regard to functionality: technological issues/usability and interface and design. Four themes (Table 1) about the specific components of the app were identified, which included facts, games, goals, and photo diary.

Overall, participants enjoyed the concept of being able to use an app to increase bioavailable iron.

However, due to user interface and design issues, they thought the current app was too cumbersome to use, and would not use it themselves.

Numerous suggestions were mentioned during the focus group discussions, including the addition of a back button, and inclusion of more colors and pictures to help decrease clunkiness and improve the interface and design of the app. Including more facts, additional games, and clarification of dietary goals are examples of suggestions previously mentioned.

The purpose of this study was to undertake a formative evaluation and identify user preferences for an app designed to improve intake of dietary iron, with the aim to aid app development and ultimately to enhance app uptake and efficacy. This information can also be used to assist in the development of a range of mobile health (mHealth) apps targeting individuals within the studied demographic (women aged 18-50) to undertake dietary change. Overall, participants liked the concept of an app focused on iron and commented that they would find it useful to help track their iron intake. This reinforces the notion that there is a market for an iron-specific app and that the target audience for the app (a population at-risk for ID) have a desire to track and improve their iron status via dietary interventions. Previous studies have shown that dietary and lifestyle interventions utilizing the app platform have also been met with similar positive reception [33-37]. These results suggest that the use of apps for health is accepted by the general population and users have a desire for uptake.

Participants wanted more facts and information, as well as the option to have an additional information section, highlighting that the majority of participants did have a desire for knowledge about iron and health. This desire for knowledge is positive, as it has been shown that knowledge is one of many influences that can affect eating behavior [38]. However, knowledge will fail to be effective when not combined with other behavior change strategies [39]. This was discussed during the focus groups, as many participants found the information was not sufficiently connected with easily understood goals or dietary recommendations.

Games have the potential to increase user knowledge, user interactivity, and engagement with the app, while maintaining engagement [27,28]. Thus, to help further knowledge acquisition while maintaining engagement, an information-seeking platform could be integrated into the games.

Users enjoyed the features of monitoring and tracking behavior, setting goals, and the ability to review progress. Many users stated that feedback was an important component that they would like to see incorporated into the app. This is consistent with the findings of similar research that young adults like monitoring and tracking features [40-42]. Feedback has been highlighted as an integral part of successful behavior change and should be incorporated into interventions delivered through apps [43].

Participants described that they wanted prompts as a reminder to use the app and complete goals. This is consistent with the literature, which indicates that prompts can be considered helpful and useful, may increase motivation, and may remind users of their goals [42,44]. However, reminders and prompts have also been considered annoying, as reminders that are perceived to be too frequent may be viewed as unnecessary [40,42]. Differences in the perceived value of reminders may be due to differences in frequency of use, as reminders considered to be unobtrusive or minimally disruptive have been positively received in other studies [45]. It is important that the user has the ability to tailor the frequency of reminders to ensure that they do not become intrusive and are found to be helpful [42].

Participants mentioned that they would like the app to be personalized and tailored to the individual. The ability to tailor the frequency of messages and the content of feedback has been a recurring theme among participants in previous studies. This research has indicated that a health app should be tailored to ensure it is flexible enough to adapt to a user’s lifestyle [33,42]. It has been noted that instant feedback may place too much pressure on users and may frustrate them if they are not achieving their goals [46]. There is also evidence that interventions with individually tailored material have greater retention rates and result in participants spending more time engaged with the interventions [44,47]. Therefore, it is recommended that tailoring or personalization be incorporated into the app during redevelopment.

Many users did not understand a few of the goals, emphasizing that goals should not assume user knowledge and should ideally be simple and explained in significant detail to ensure that they are understood and are achievable by the user. Goals that are considered general, which do not provide feedback to notify users on goal progression, have been shown to be less effective than goals that are specific [48].

Many participants suggested that they would have liked the weekly goal review to be an overview or report about progress toward their goals, ideally in graphical form. This finding is not unique; participants in other health-related research on weight and diabetes management have similarly found monitoring to be valuable [49,50]. It has also been found that app users prefer graphical feedback to feedback in other formats [42]. Thus, it may be beneficial for feedback and monitoring in the app to be displayed in a graphical format, which is possible through the mobile phone app platform [42].

Participants stated that rewards would encourage engagement with the app and adherence to dietary goals. Rewards that recognize an achievement may help to motivate participants to continue to use the app and help to maintain user engagement [44,51].

Modifications based on the suggestions from participants in this study were made to the WIZE app. Additional colors and pictures were added throughout the app to increase its appeal; additional links between components of the app were added to increase usability; the goals were clarified and restructured; and games were modified to include further information about iron. Postmodification screen shots of the app can be seen in Figures 4 and 5.

The majority of participants were recruited from one area of Deakin University, Melbourne Burwood Campus, Australia; therefore, it is unknown if these views are reflective of the broader population. The sample was predominately younger females with a high level of education. Participants having access for only 2 weeks before participating in a focus group may have resulted in different opinions than if the app had been used over a 4-week trial (the period over which goals were designed to be implemented). A further potential limitation was that the app was only available on the Android mobile phone platform. Users of this specific platform may not represent all mobile phone users.

Participants expressed interest in an app to increase their intake of bioavailable iron and data obtained aided the redevelopment of the app. In terms of components, goals, feedback, and self-monitoring were considered valuable and should be incorporated into future app interventions. The value of implementing other features such as reminders and prompts is unclear and may depend on the individual. Information and insights obtained from this study help to clarify the acceptability and user preferences of apps as a platform for behavior change interventions and may help guide and inform the development of future app interventions.