Yeah, I am ramping up my efforts to become fully self-employed (I'm a part-time freelance web designer) and I would like to use my future hypothetical mobile phone for phone calls with customers (right now I mostly use email). My other objective is to use my phone for streaming live video across the internet. The utility of a phone is undeniable- might just "pay for itself" from my point-of-view!
The struggle I have had is determining what these two things are worth (1: ability to talk with customers when I'm away from my computer. 2: Uploading live streaming video from anywhere.), because value is subjective. The great thing about internet forums, is I get to bounce off ideas and have people confirm with me that certain prices for certain things are a rip-off or are reasonable or certain products are inferior/superior to others.
Congrats onto your endeavors! Self-employment is not only a royal pain (imho), it's also very difficult, very expensive, and yet oh-so-rewarding. If you do attempt self-employment (as in starting a legalized business), I advise to research the proper documentation first. Then build a plan, including a financial budget. Then tackle the mainframe of your work (websites, email, hardware, software, etc). Might also want to familiarize yourself with a financial tracking program to see if you're profiting, assuming you want/can write-off your cell phone expense as a business expense. A small $50 monthly plan turns into a large $600 bill at the end of the year. Even a pay-as-you-go plan might be sufficient.
All-in-all, the more you use your data plan, the more integral it becomes as a part of your daily life. When I wake up, I no longer go to the laptop to check PokeGym; I use my mobile phone that woke me up a few minutes ago. When a customer emails a concerning message, I can reply instantly to their concern whether I'm out shopping or out dining. If you're the kind of person, such as myself, who likes taking video/pictures and uploading them in real-time, who likes surfing the web wherever and whenever, who likes playing games on-the-go, who likes planning day-to-day operations on their mobile, then a data plan is for you. Otherwise, you might opt for a phone w/ data capabilities and add a plan later.
Regardless of whether you get a data plan or not, consider the methods of charging and battery life of your phone. Internet and GPS just KILL battery life on a cell phone. My phone has a USB micro port that allows me to charge from any USB capable device. But I know some phones require a special cable of their own, which may sucker you out $25 for an accessory.
Odds are you'll be getting a smartphone either way. Struggle #1 isn't much of a problem for any phone, regardless of data plan. So it's up to Struggle #2 to determine whether you need a data plan or not. I mean, you could capture video on your phone, wait the half hour to get back home, and upload it from your PC. Unless, you really, really love using uStream.
