  Increasingly emerging technologies in micro-electromechanical systems and
wireless communications allows a mobile wireless sensor networks (MWSN) to be a
more and more powerful mean in many applications such as habitat and
environmental monitoring, traffic observing, battlefield surveillance, smart
homes and smart cities. Nevertheless, due to sensor battery constraints,
energy-efficiently operating a MWSN is paramount importance in those
applications; and a plethora of approaches have been proposed to elongate the
network longevity at most possible. Therefore, this paper provides a
comprehensive review on the developed methods that exploit mobility of sensor
nodes and/or sink(s) to effectively maximize the lifetime of a MWSN. The survey
systematically classifies the algorithms into categories where the MWSN is
equipped with mobile sensor nodes, one mobile sink or multiple mobile sinks.
How to drive the mobile sink(s) for energy efficiency in the network is also
fully reviewed and reported.
