  Context. Multiple automated techniques have been proposed and developed for
mobile application GUI testing aiming to improve effectiveness, efficiency, and
practicality. The effectiveness, efficiency, and practicality are 3 fundamental
characteristics which testing techniques are built upon, and need to be
continuously improved to deliver useful solutions for researchers and
practitioners, and community as a whole.
  Objective. In this systematic review, we attempt to provide a broad picture
of existing mobile testing tools by collating and analysing their conceptual,
and also performance characteristics including an estimation of effectiveness,
efficiency, and practicality. Method. To achieve our objective, we specify 3
primary, and 14 secondary review questions, and conducted an analysis of 25
primary studies. We first individually analyse each primary study, and next
analyse the primary studies as a whole. We developed a review protocol which
defines all the details of our systematic review.
  Results. From effectiveness, we conclude that testing techniques which
implement model-checking, symbolic execution, constraint solving, and
search-based test generation approach tend to be more effective than those
implementing random test generation. From efficiency, we conclude that testing
techniques which implement code search-based testing approaches tend to be more
efficient than those implementing GUI model-based. From practicality, we
conclude that the more effective a testing technique is, the less efficient it
will be.
  Conclusion. For effectiveness, we observe that the existing automated testing
techniques are not effective enough, and currently they achieve nearly half of
the desired level of effectiveness. For efficiency, we observe that current
automated testing techniques are not efficient enough.
