Ключевые слова: background, business, call, card, cell, cellphone, cellular, chip, communication, concept, connect, connection, device, dial, digital, electronic, equipment, gsm, information, internet, lock, macro, micro, mobile, mobility, modern, network, number, object, operator, phone, prepaid, security, service, sim, sim card, simcard, smart, smartphone, talk, technology, telecommunications, telephone, wireless,