We introduce a novel, data-driven way for predicting battery consumption of apps. The state-of-the-art models used to blame battery consumption on apps are based on micro-benchmark experiments. These experiments are carried out on controlled setups where one can measure how much battery is consumed by each internal resource (CPU, bluetooth, WiFi...). The battery blame allocated to an app is simply the sum of the blames of the resources consumed by the app. We argue that this type of models do not capture the way phones work "in the wild" and propose instead to train a regression model using data collected from logs. We show that this type of learning is correct in the sense that under some assumptions, we can recover the true battery discharge rate of each component. We present experimental results where we consistently do better predictions than a model trained on micro-benchmarks.