Nothing in particular - he may have just been busy or just giving sometime between the date and when he was prepared to call you again - don't read into it.
It can mean some date in the future, with the date itself not specifically mentioned. You may want to leave doing something until a later date, for example.
well, dont be mean to her, try to be her freind first than later you might find she likes you and you'll date lol.
I hope you do not mean cell phone calls because they did not exist until nearly 2000 years after Peter died. However, God did call him to be an apostle and, later, to be to leader of the Church - the first pope.
If he calls you within the next day or 2, then he likes you and was being straightforward when saying he'd call you later. No hidden message, there. Unless you really are familiar with the person, when someone says 'later', it is not a commitment to a time frame of, if or when you will hear from them, and it's usually a nice way of saying, Good-bye.
Postpone
Since most people would find it weird and distasteful to date their sister, I would say "no".
It means he wasn't able to come to the phone when you called. Relax.
He thinks you're disgusting =(
it means that he thinks they are a pieice of $#!t duhh! okay now.... 7 minutes later ...... 9 minutes later... bye.
The matter is being "re-schdeuled" unitl a later date
That he has a surprise for you and that he's going to show it to you on your first date.
It means that he is not your boyfriend!