Ted72, being able to expand the memory on your phone is a must. I do it with my phone often. With the LG Zone 4 you can use a MicroSD card up to 2 TB (Terabytes). When you buy a memory card, as for a MicroSD 128 GB memory card. Take a look at page 19 of the LG Zone 4 user guide for instructions on Inserting and Removing a Memory Card.
I hope this information is beneficial.