Background: People with dementia experience problems to maintain autonomy and self-determined mobility. Assistive technology devices, if adapted to the specific needs of this user-group, may support people with dementia and help them maintaining daily functioning and independence. Objective: This study aimed to examine the future users' perspective on function and design requirements for technical navigation assistants to support outdoor mobility in people with cognitive impairment. Method: Within a user-centered design approach we conducted semi-structured interviews on mobility behaviour and technology affinity with 14 people with mild cognitive impairment or mild to moderate dementia. Qualitative content analysis as described by Mayring was used to analyse the data. Results: Nearly all of the participants expressed the need for self-determined mobility and all participants used technical devices in their daily life. Five of 14 participants had experienced phases of disorientation outside their homes, resulting in discomfort and a reduction or avoidance of outdoor activities. The participants' requirements for a technical navigation assistant comprised the following features: Integration of safety services; customisable functions, a legible display, a small, unobtrusive design of the device (e.g., a smartphone or watch), and additional support for the selection of and adherence to compensation strategies. Despite previous experiences with navigation systems, participants did not use them. This indicates the need for innovations in this area. Conclusion: People with dementia provide us with essential expert insights into dementia-related mobility constraints and requirements for the design of technical navigation assistants. These insights will help to improve usability and acceptance of such technologies by the intended users.