Come to think of it
Definition 1 of 1
Pro Tip 1/3Reflective Moment
Indicates the speaker is reconsidering or just realized something during the conversation. 
We could watch a movie, come to think of it, didn't we see that one already?
Pro Tip 2/3Conversation Flow
Often used to smoothly change the direction or topic within a conversation. 
She's very talented, and come to think of it, her brother is a great musician too.
Pro Tip 3/3Colloquial Reminder
Signals a spontaneous memory or point that supports or contradicts the current discussion. 
His advice was helpful, but come to think of it, he had a different agenda.