Had a first date last night. Neither one of us looked at our phones the whole time until we looked around and realized they were cleaning up the restaurant.
The best way to show clear interest is to be a little handsy. If you're interested, touch your date. Breaking the touch barrier and initiating some physical contact, even just a little, increases the intimacy of the date.
Look back just before disappearing from view at the end. Like, lets say you are getting into a cab.
Once was hanging out with a girl and finally got to the point of kissing her, but did it pretty lightly because I was still nervous. She looked at me and asked.
Sometimes you think we don't care because we don't sit there like your girlfriends and chat with you about how happy we are to have met you, but that isn't the case.
I've had a few that have turned up late but I've always had a text update with an apology.
"Be interested in what I'm saying. Kissing me. I'm a simple man."
On one of the best dates I've ever had, the woman kissed me as soon as I opened the door and we'd introduced ourselves, to take the pressure off me worrying about a first kiss at the end of the night. I loved it.
Show actual interest while on the date and past it. Not saying you need to be all over the place, listening to everything and shit, just show genuine interest in the overall event