Re: What Functions Does a Smartphone Still Have if U Take Out the SIM
Android phones have an option to turn off the data connection. Also you could just turn on the airplane mode. That effectively blocks all connection outside. Unfortunately that also blocks wifi connection.
But to answer to your original question, I pulled SIM card out of my own Android phone today (Sony xpress mini pro) and it works just fine without it. Only phone functions and those related to mobile data are disabled.
Edit: Forgot to mention that emergency calls still work.
"God runs electromagnetics by wave theory on Monday, Wednesday, and Friday,
and the Devil runs them by quantum theory on Tuesday, Thursday, and
-Sir William Bragg