This paper presents a study that explores the relation between how the choice and use of an app depends on the network performance. While the relation between smartphone user behavior and contextual factors has been explored in previous research, the mobile networks’ influence on the smartphone user behavior is largely unknown. Through analysis of a data set collected from ~1500 users using Ericsson Apps, a logging tool for Android phones, the results show indeed that data demanding apps have a strong positive correlation between the relative usage and the network performance. For example, the results demonstrate that users are around 1.4 times more likely to use YouTube on LTE than on EDGE. This information, combined with an understanding of contextual factors, can be used to optimize networks by adapting the network performance to the user’s requirements and real levels of consumption. Furthermore, it can be possible to tune services pro-actively and improve the Quality of Experience (QoE).