Seeking a planner I can physically write in that will sync to an online calendar

I am seeking a product I cannot see to find after some googling. I currently use a paper planner that lives on my desk , but when I am traveling between work sites I don't physically have this planner with me so it is hard for me to schedule things. Is there a planner I can physically write in (in tablet-like form or otherwise) that will sync up with a digital calendar? I want to be able to write my scheduled activities with my hand, then view them on my phone later.