This paper analyzes the requirements of mobile health appli-cations concerning real-time criteria and describes the cur-rent state of real-time capabilities on constrained devices and low-power networks. Based on this analysis we observe that for these applications real-time capabilities are not only required per system, but also for the entire distributed sys-tem. Furthermore, we describe which technologies are avail-able for the network stack, the software platform, and the hardware in order to fulfill these requirements. From the requirements on the network stack, following a top-down approach, we derive hardware prerequisites. We then con-duct measurements on typical IoT hardware and operating system. We conclude that it is feasible to fulfill the identified prerequisites.