The sole source of info for this blog was the thread dedicated to the Karbonn A5 (and A7) smartphone at forum.xda-developers.com ( http://forum.xda-developers.com/showthread.php?t=1788936 ).
Everything that is needed to ROOT and MOD the A5 is there, if you have
the patience to trawl through the many posts. A huge thanks to all those
who contributed their time and knowledge there. We, the end users of
Karbonn A5 will remain indebted for the selfless service.
I have done below is collate info from those relevant posts that
pertain specifically to A5 and its rooting and modding process. Please
note this is a layman's description of a tech issue, so expect errors.