The rapid global proliferation of smartphones and their associated information infrastructures has been a defining feature of the past decade's global crises. Yet, while the digital is now a topic of keen interest for scholars working on virtually everything that constitutes the international, the smartphone as an object of study in and of itself has been largely elusive. Moreover, emerging studies of contemporary crisis, such as ‘polycrisis’, often downplay the role of the digital. How can we conceptualize the ambiguity and ubiquity of the smartphone, as it impacts diverse fields of human action, from war to humanitarianism to democracy? And how can we empirically study this phenomenon and its distributed effects? We contend that smartphones are both embedded in and embed global crises. We conceptualize this as ‘global crisis ecologies’: new spaces that are not simply geographical, or easily framed in terms of North/South divisions, and that include the informational infrastructures that mediate the way crisis is apprehended. This framing helps us understand how multiple civilian, state and non-state actors at different societal levels participate in crises through everyday smartphone use. It foregrounds how the speed, audio-visual capabilities and inherent scalability of smartphones shape how crises are perceived and managed