FreedomPop is operating on a scamming shady level by not being honest about what they are selling.

They don't give you a real phone number, just some app you need to use to call.

Avoid them.

Edit: Is it how hacker news community is? downvoting because I tell the truth how their service is? I had the experience of getting charged for months without warning. They use your credit card, instead of direct debit in the UK so even more annoying for cancelling. And no requiring customer to read every details of your contract is not fair. Fair is an important part of any contract, finding you are getting a VoIP number is not normal.