Are online food delivery systems persuasive? The impact of pictures and calorie information on consumer behavior

Purpose - The study's purpose was to examine the role of two main factors in the design of online food delivery systems (OFDS) user interfaces: the display of pictures and calories - on consumers' attitudes toward online food delivery systems, intentions to use such systems, spending on a food item and tipping behavior. Design/methodology/approach - The study is grounded in the elaboration likelihood model. A 2 x 2 randomized post-test only between-subjects experimental design manipulated the types of pictures (food item only vs consumers eating a food item) and calorie information display style (numbers vs activity symbols) to determine whether they influence consumers' attitudes, intentions to purchase, spending and tipping behaviors. Findings - The results show that the calorie display style influences consumers' intentions to use such systems and consumers' tipping behaviors toward the delivery driver. It was also found that the type of picture shown to consumers influences their intentions to purchase through ODFS, such that pictures of consumers enjoying a product is more effective in stimulating intentions to purchase than pictures containing only the food items. Research limitations/implications - This study advances the current knowledge on web design for restaurants wishing to distribute via online food delivery systems. Moreover, this study extends the literature on persuasion in online environments by focusing on foodservice - an area that only recently has undergone substantial distribution online. Finally, this study advances the literature on tipping behavior. Practical implications - This study provides several contributions for both restaurants and online food delivery system designers. Specifically, it illustrates exactly how specific elements in the design of the web interface and the message targeted at consumers influence consumers' behavior. Most importantly, this study provides insight into tipping behaviors for the delivery driver. This is important because the delivery driver is an important participant in the new value chain of restaurant delivery. Originality/value - As the first study to develop an experiment that tests these important design conditions, this study offers several critical theoretical and practical implications. This study is the first attempt to examine various ways to present persuasive information in an OFDS in order to stimulate consumers' behaviors. Moreover, this study illustrates that the use of website design that enhance social presence is critical to website effectiveness in OFDS.