But if I were to guess, I would say that dual sim 'active' means both networks/phone numbers can receive calls while the phone is turned on. Standby probably means one always has to be preferred over the other.
Ask this @ howardforums.com for the straight dope on what it actually implies.
What is the difference between dual sim standby and not dual sim standby?
I am not asking for difference between dual sim active and dual sim stand by.