Soldiers, first responders and other personnel operating at the tactical edge increasingly make use of mobile devices to help with tasks such as face recognition, language translation, decision-making and mission planning. Tactical-edge environments are characterized by limited resources, dynamic context, high stress and poor connectivity. This paper focuses on three architecture patterns that address these conditions. The Data Source Integration pattern uses server-side standardized
definitions of live or cached geo-located data feeds that can be customized and filtered on a single, map-based user interface on a mobile device. The Group Context Awareness pattern uses context obtained from groups of handheld devices operating as part of a team to make sure that the right information is displayed to the right soldier at the right time. The Cloudlet-Based Cyber-Foraging pattern uses cloudlets as code-offload elements to optimize resources and increase computation power of mobile devices. Cloudlets are discoverable, localized, stateless servers running one or more virtual machines on which users can offload resource-intensive computations from their mobile devices. Prototype applications have been implemented for each of these patterns. Experiment results and participation in exercises have shown the effectiveness of the patterns in addressing the challenges of resource-constrained environments.