Smartphone Without Carrier?

I have recently considered getting the OnePlus One as my first smartphone, however I don't call or text much. Maybe it's a stupid question, but I was wondering if I could still use wifi for things like music from a NAS, Skype, web browsing, etc without having to pay whatever ungodly amount they charge for data (not to mention the general BS involved).

Thanks.

If you don't pay for service you'll only be able to use wifi. But if that's all you need it should work well. 

Boss. Thanks for the help.

This is actually how I use my Galaxy S3 with Cyanogenmod. I used to have service, but since I started working from home I canceled the service. I actually use Google Voice and it integrates with Hangouts now. So everyone has my Google Voice number, they can text, picture message, or call the number, and if I'm connected to WiFi, it'll come through on my phone via Hangouts.

The only downfall is that for some reason the option to ring in hangouts keeps getting unchecked on my phone.