You are right Muddassir Husain mobile phones have became a common household requirement as now a days many things are done on our mobile phones. Now smartphones have also become a gaming console as they runs on Android. And PC like games have started coming for Android platforms like GTA, Modern Combat series, Asphalt series, NFS series and many more.
Besides this, smartphones with high camera features have replaced actual cameras, isn't it? Moreover, now we don't need bulk of files for any purposes (official or personal) as we can carry them easily on our smartphones. The thing which made these smartphones more addictive is WhatsApp. So such examples shows why landlines are not currently active in most of the households.
I find that the harder I work, the more luck I seem to have.