Abstract The major promise of multimodal user interfaces for older users is that they have the choice to select the input modality (or combination of modalities) that best fits their needs and capabilities. Two studies investigated if multimodal interfaces with touch, speech, and motion control fulfil the expectation of being superior to the interaction with single modalities in a mobile device regarding efficiency, robustness, and user satisfaction. The results of both studies show a superiority of multimodality over the single modalities speech and motion control and a slight advantage over touch, which was the modality most frequently used even in the multimodal condition in which any modality or a modality combination could be chosen. Differences between old and young users were only shown for motion control which turned out to be less suitable for older people. The major promise of multimodality for inclusive design thus does not seem warranted so far. However, other applications and contexts of use need to be investigated.