  Precision measurements comparing the fundamental properties of conjugate
particles and antiparticles constitute stringent tests of CPT invariance. We
review recent precision measurements of the BASE collaboration, which improved
the uncertainty of the proton and antiproton magnetic moments and the
comparison of the proton-to-antiproton charge-to-mass ratio. These measurements
constitute the most stringent tests of CPT invariance with antiprotons.
Further, we discuss the improved limit on the antiproton lifetime based on the
storage of a cloud of antiprotons in the unique BASE reservoir trap. Based on
these recent advances, we discuss ongoing technical developments which comprise
a coupling trap for the sympathetic cooling of single (anti-)protons with
laser-cooled beryllium ions, a transportable trap to relocate antiproton
measurements into a high-precision laboratory, and a new experiment to measure
the magnetic moment of helium-3 ions, which will improve absolute precision
magnetometry.
