Yeah, I dropped my cell plan and went to ipad mini 4 only a month ago.
For service I am using T-Mobile's free 200MB/month. Last month I used 100MB.
I transferred my phone number to Google Hangouts for $20 and use hangouts for calls in and out.
For friends/wife on Apple products, I use facetime voice for calls
For apple people I use Messages for texting and for non-apple messages I use hangouts.
Oh, as long as I am in a wifi area, I can use my old iphone 5 (with no cell/data plan) for calls and messages. It basically acts in parallel with the ipad.
I am always in wifi areas so this all works well for me.