Do I need WIFI to connect to the garagedoorbuddy box to open and close the garage door?

Yes. This is the default option. Please make sure you can detect your WIFI signal on your phone outside of the garage. For advanced users, you can use router port mapping to expose garagedoorbuddy box to the Internet. Then you can connect to the garagedoorbuddy box to open and close the garage door from any cellular network. You can also refer to GDB Advanced Mode