If you want to observe a target group over a longer period of time, whether to learn about general or topic-specific attitudes and behaviour, a diary study is ideal. For this, we use versatile and customised question and task formats. In addition to the possibility of keeping a diary of the behaviours of interest over several weeks, participants can upload photos or videos, answer integrated questions and write short essays on relevant topics. In addition, participants can also be given concrete tasks to work on. These tasks can also trigger scenarios that rarely occur spontaneously, e.g. a contract conclusion or a cancellation. If one wants to approach the customer experience in mobile contexts, a scavenger hunt is recommended as a supplementary module in which tasks build on each other and their processing takes place sequentially. This is ideal for surveying along the customer journey or for customer journey mapping. For appropriate target groups, e.g. less internet-savvy sections of the population such as senior citizens, we are also happy to conduct offline diary studies. In these cases, the respondents can participate by paper and pencil.