  People nowadays are increasingly dependent on mobile phones for daily
communication, study, and business. Along with this it incurs the low-battery
anxiety (LBA). Although having been unveiled for a while, LBA has not been
thoroughly investigated yet. Without a better understanding of LBA, it would be
difficult to precisely validate energy saving and management techniques in
terms of alleviating LBA and enhancing Quality of Experience (QoE) of mobile
users. To fill the gap, we conduct an investigation over 2000+ mobile users,
look into their feelings and reactions towards LBA, and quantify their anxiety
degree during the draining of battery power. As a case study, we also
investigate the impact of LBA on user's behavior at video watching, and with
the massive collected answers we are able to quantify user's abandoning
likelihood of attractive videos versus the battery status of mobile phone. The
empirical findings and quantitative models obtained in this work not only
disclose the characteristics of LBA among modern mobile users, but also provide
valuable references for the design, evaluation, and improvement of QoE-aware
mobile applications and services.
