To build energy-efficient apps, there is a need to estimate and analyze their energy consumption in typical usage scenarios. The energy consumption of Android apps could be estimated via software-based and hardware-based approaches. Software-based approaches, while easier to implement, are not as accurate as hardware-based approaches. The process of measuring the energy consumption of an Android app via a hardware-based approach typically involves 1) setting up a measurement environment, 2) executing the app under test on a mobile device, 3) recording current/voltage data via a hardware device to measure energy consumption, and 4) cleaning and aggregating data for analyses, reports, and visualizations. Specialized scripts are written for selected hardware and software components to ensure reliable energy measurements. The energy measurement process is repeated many times and aggregated to remove noise. These steps make the hardware-based energy measurement process time-consuming and not easy to adapt or reproduce. There is a lack of open-source tools available for developers and researchers to take reliable energy measurements via hardware devices. In this paper, we present and demonstrate ARENA, a support tool that enables developers and researchers to connect to a physical measurement device without leaving the comfort of their IDE. Developers could use ARENA during development to compare energy consumption between different apps or versions of the same app. ARENA calculates energy consumption on an Android smartphone by executing a test scenario on the app under development. Further, ARENA helps aggregate, statistically analyze, report, and visualize the data, allowing developers and researchers to dig into the data directly or visually. We implemented ARENA as an IntelliJ and Android Studio plugin.