I have developed my applet, installed and tested successfully on my target smart cards (NXP J3R180). Now I need to change card default keys as a final step, but I need it to be done along with sending personalization APDUs to the card.
Now, my question is "How to change card's default keys from 404142...4F
to a desired key by just sending APDUs to the card (possibly to ISD)?".
There is an APDU command just for that: PUT KEY
You can read up all the details in the GlobalPlatform Card Specification, https://globalplatform.org/specs-library/