cell phone data plan

How many of you home business operators actually use the data plan on your cell phone? Is it simply an added expense a new small business operator can do without or is it a necessity? I will be in my home office about 75% of the time, and out about 25%. Trying to make a decision. Didn't know if this was the right forum for this question. My apologies.
Thanks for the responses to come.

See original post by JustRay