If Ooma provides free phone over the internet. Why is their a 3000 minute limit per month? Aren't the calls carried over the internet? There should actually be no limit.
Yes the calls are carried over the Internet.
What's free about the Internet?
You can't do anything with an Ooma by itself. You also need an Internet connection and a "phone company" of some type.
You pay to get the Ooma device and as far as I know you also have to use Ooma as your phone company. You are locked into them once you buy the Ooma. You can't choose another phone company.
There are competing devices such as from Obi that cost less up front and also let you choose your phone company. The phone companies have various calling plans and packages just like any phone company would. I don't use the phone much--maybe an hour or 2 a month.
I use Callcentric as a "phone company".
My total costs are 3.45 per month plus about a dollar an hour that I'm actually on the phone (incoming or outgoing; local or national; including 911). If I used the phone thousands of minutes per month, I'd certainly get a different plan with the same phone company. Obi has several devices and a basic one-line model can be had for as low as 30 bucks on sale at Newegg.
Prior to getting the Obi, I was using Cox phone service as part of my TV/Internet package. Cox phone is also "over the Internet" (VOIP). The Callcentric service is just as reliable. I still use Cox as my Internet provider and if my Internet goes down I have no phone service. But that's nothing that Callcentric or Obi can control. The Cox phone service was about $15 per month.
I just got rid of Cox cable TV as well and am now using a Roku 3 in addition to over the air stations through a $30 indoor antenna. My Cox monthly bill has gone from 201 down to 75. The Roku was about 90--a one-time expense.