Smartphones are ubiquitous devices with millions of units are sold around the globe every year. To meet the growing performance needs of innovative applications, smartphones industry has shown tremendous developments in computing, storage capacity, communication, and battery power technologies. The integration of sensors has turned smartphones into powerful sensing methods with unlimited opportunities for devising novel applications for solving realworld problems. This has given rise to a new area of research called smartphone sensing which have potential applications in different domains including lifelogging. However, continuous and inefficient usage of sensors in lifelogging can consume significant amount of battery power and can drain out fully charged battery within a few hours. In this paper, we have presented the importance of smartphone sensors in monitoring users' daily life activities and their usage effects on smartphone battery lifetime. For this purpose, an Android app Energy Monitoring System for Smartphones Sensors (EM3S) is developed. EM3S is experimented in several real world scenarios for estimating smartphones sensors battery power consumptions information. It is found that smartphone sensors consume varying amount of battery power during different daily life activities. However, collectively, they can affect smartphone performance and is a major hurdle for smartphone sensors-based applications. This study is aimed to help researchers, manufacturers and developers in exploring optimal sensors battery power consumption methods while developing pragmatic smartphone sensors-based applications.