Table 2.

Codes, categories, and theme from qualitative content analysis of 12 group interviews.

Code	Category	Theme
The design of the app matters The app was difficult There were technical problems with the app/mobile phone Unclear with feedback Unclear/frustrating with reminders Unnecessary functions Is the feedback correct? Difficult to find the feedback Difficulty with the questions in the evening Type of mobile phone matters Wants to record exercise	Difficulties of using the mobile phone app	To overcome the barriers
App is simple/good/fun Good and interesting with the results Good with the questions in the evening Advantage with mobile phone	Benefits of using the Mobile phone app
It is easy to forget Easier to record in the evening Difficult to record (in general) Combines techniques to remember You do not give up You have to think about when you eat and when to record You get tired Impractical sometimes The recording was fun/OK	The process of recording
Good with pictures Good selection of foods There is a need for more composite dishes Had to take something similar Difficult to record food with lots of ingredients Difficult to record sandwiches Difficult and unnecessary to record small meals Difficult/hard to estimate amounts Unclear what should be recorded Foods/dishes were missing Hard/difficult to record if you do not know content/type Hard/difficult to choose between many alternatives	Recording correctly
Improve dietary intake Avoided eating so you do not have to record	Dietary intake was affected
Reflects over the diet The days of recording were not representative	Awareness of diet and physical activity habits
Lack of interest Unclear with the study/methods Worry about focus on weight and dietary habits	The study is not for me