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Despite their relatively high intrinsic brightness and the fact that they aremore numerous than younger OB stars and kinematically colder than older redgiants, A-type stars have rarely been used as Galactic tracers. They may, infact, be used to fill the age gap between these two tracers, thereby allowingus to study the transition between them.  We analyse Galactic disc structure and kinematic perturbations up to 6 kpcfrom the Sun based on observations of A-type stars.  This work presents a catalogue of A-type stars selected using the IGAPSphotometric survey. It covers the Galactic disc within $30^{o}\leql\leq215^{o}$ and $|b|\leq5^{o}$ up to a magnitude of $r\leq19$ mag with about3.5 million sources. We used Gaia Data Release 3 parallaxes and proper motions,as well as the line-of-sight velocities, to analyse the large-scale features ofthe Galactic disc. We carried out a study of the completeness of the detecteddensity distributions, along with a comparison between the $b<0^{o}$ and$b>0^{o}$ regions. Possible biases caused by interstellar extinction or by theusage of some kinematic approximations were examined as well.  We find stellar overdensities associated with the Local and the Perseusspiral arms, as well as with the Cygnus region. A-type stars also providekinematic indications of the Galactic warp towards the anticentre, whichdisplays a median vertical motion of ~6-7 km/s at a Galactocentric radius ofR=14 kpc. It starts at R=12 kpc, which supports the scenario where the warpbegins at larger radii for younger tracers when compared with other samples inthe literature. We also detect a region with downward mean motion extendingbeyond 2 kpc from the Sun towards $60^{o}<l<75^{o}$ that may be associated witha compression breathing mode. Furthermore, A-type stars reveal very clumpyinhomogeneities and asymmetries in the $V_Z$-$V_{\phi}$ velocity space plane.

Exploring the structure and kinematics of the Milky Way through A stars