Prepaid SIM card

What is the best use of the extra credit in the prepaid SIM card. You may answer by “Using it” but please think again. Many of us can’t stop using their mobile phones even during their vacations. I was using my original SIM card during my international travel but I learned (the hard way) that roaming services are very expensive once I mad it back home and got the first phone bill. I bought a cheap mobile phone and used it as a secondary mobile phone with a prepaid SIM card from the country I am traveling to. My international roaming service costs came down drastically, so I found myself calling home more often because of the low cost of the international calls when using the prepaid SIM cards. The only problem with such plan is the remaining credit on the SIM card during the last day of your travel. I noticed many people use up their credit by calling their friends and relative or somebody they just want to wast time with. They do these annoying calls in the airport boarding gates or on the airplane just before taking off. You will be tired and look for peace but people around you keep on telling their life stories over the phone to somebody in another time zone. The women next to me in the plane is giving a detailed report to her friend back home just to use up the prepaid credit. I know now what she did during her vacation to the last detail. And almost half of the airplane overheard her annoying conversation. When she hang up the mobile phone she asked her daughter if her phone also have unused credit?
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