Long answer: According to the International Telecommunication Union (ITU), there were an estimated 5 billion unique mobile phone users in the world as of January 2018. However, it is important to note that this number does not necessarily equate to the number of individual subscribers, as some people may have more than one mobile phone or SIM card. Additionally, the number of cell phone subscribers can vary by country and region. For example, according to Statista, the number of mobile phone users in the United States was approximately 266 million in 2018. Overall, while there is not a definitive global estimate for the number of cell phone subscribers in 2018, it is clear that mobile technology continues to have a significant impact on the way people communicate and access information worldwide.