Mobile computing devices, in particular smartphones are powered from Lithium-ion batteries, which are limited in capacity. With the increasing popularity of mobile systems, various text input methods have been developed to improve user experience and performance. Briefly, text input method is a user interface that can be used to compose an electronic mail, configure mobile Virtual Private Network, and carryout bank transactions and online purchases. Efficient energy management in these systems requires an extensive knowledge of where and how the energy is being used. This thesis investigates the energy consumption of text input methods on various smartphones. Hence, the authors modeled the energy consumption profile of text input methods on smartphones and analyze the energy usage benchmarks of the battery. This thesis presents a systematic technique to conduct application specific measurements. The data analysis showed substantial variations in the energy consumptions of various text input methods on a smartphone. / The main objective of this research is to find a systematic and measurement based method to evaluate the energy efficiency of the selected text input methods used on smartphones namely: SwiftKey, Swype, and Zimpl. Using Power Monitor equipment and MATLAB, the energy consumption log files of the text input methods were collected for each of the smartphones, and analyzed. This research introduces an optimized technique to carry-out application specific test on smartphones. It is hoped that the thesis will be beneficial to smartphone battery manufacturers and developers of text input techniques on how to make users’ smartphone battery last longer.