They work by selling you a SIM card and offer services for free (via advertising). Too good to be true, I never fell for it myself but the wife did and she got five months of services before they vanished. More than I expected!!!!
The company was likely well aware they were in difficulties but up until the minute they shut down just a few hours ago they were still selling SIM cards for £20 a piece.
I've read on forums people have been angry that they purchased a SIM card a few days back, registered it this evening and got literally a few minutes of service before they shut down.
Disgraceful company and I hope the irresponsible owner(s) are held accountable, they have continued selling and making money while know the crap they were in.
Glad I stayed with GiffGaff.
Just a word of warning for those not aware, Ovivo has vanished into thin air!!