Mobility and independence are key aspects for self-determined living in today's world and demographic change presents the challenge to retain these aspects for the aging population. Augmented Reality (AR) user interfaces might support the elderly, for example, when navigating as pedestrians or by explaining how devices and mobility aids work and how they are maintained. This poster reports on the results of practical field tests with elderly subjects testing handheld AR applications. The main finding is that common handheld AR user interfaces are not suited for the elderly because they require the user to hold up the device so the back-facing camera captures the object or environment related to which digital information shall be presented. Tablet computers are too heavy and they do not provide sufficient grip to hold them over a long period of time. One possible alternative is using head-mounted displays (HMD). We present the promising results of a user test evaluating whether elderly people can deal with AR interfaces on a lightweight HMD. We conclude with an outlook to improved handheld AR user interfaces that do not require continuously holding up the device, which we hope are better suited for the elderly.