This chapter discusses indexical visualization and design as an alternative approach to delivering information. Visual representations of abstract data are ubiquitous in contemporary culture. Contextual and location-referenced information is usually delivered within the narrow constraints of a smartphone display. In the domain of ubiquitous information, arbitrary symbolic languages are bound to fail without established visual conventions. Design choices for indexical visualizations can be illustrated through the mechanisms used in analog instruments for measurement. Indexical visualization therefore aims to increase the legibility of the index through external constraints. The manifestations of indexical representations can be diverse, depending on their context and medium. Most traditional analog instruments for measurement, recording and displays are indexical to varying degrees; a sundial is arguably more than a mechanical clock. The framing in indexical visualizations is a matter of explicating implicit and ambiguous information. Ambiguity is a necessary trade-off for the sake of minimizing the causal distance to the object.