What “Inna di morrows” means
Inna di morrows means "see you tomorrow", literally "in the morrow". It's a parting line for the end of the day when you expect to see the person again the next day.
Examples
Mi gone, inna di morrows!
I'm off, see you tomorrow!
Aright, inna di morrows.
Alright, see you tomorrow.
How to use it
Said at night or at the end of a working or school day, usually between friends, co-workers and family.