Send FormIT including local storage data

I have a form build using formIT with name, telehone, etc... and previously I saved some data on local storage.

How can I send the local storage data included in the email?

May be using a hook? in that case how?

can anyone guide me please?
Thank you! [ed. note: Ysanmiguel last edited this post 7 years, 2 months ago.]