Revisiting the battery level indicator of mobile devices

Mobile device users tend to extend the device’s usage time by checking the battery level frequently via the battery level indicator (BLI) and adjusting their device usage patterns. This behavior is based on the assumption that the BLI is accurate. In this paper, we define four requirements that a user would expect for the BLI and define BLI anomalies that violate these requirements. We found various kinds of BLI anomalies in commercial smartphones. The key cause of a BLI anomaly is that the battery state changes dynamically depending on various factors, yet the existing BLI system is limited in delivering the battery status adequately. To address this problem, we propose a new BLI that defines the battery capacity as active, spare, and dead. The experiment results for the commercial smartphones show that with the proposed BLI system, BLI anomalies are removed, and accurate battery information is delivered to users.