[Top 20 US stock turnover: Research institutions said that from next year, the average service life of the iPhone will be 8 years] The third Apple closed down 0.34%, trading $7.785 billion. Research firm CCS Insight released a report today saying there will be 1.3 billion iphones in use by the end of 2023, with more than 50 per cent of them being second phones. The prediction underscores the growing longevity of Apple's smartphone. From 2024, the average iPhone will last eight years, according to CCS Insight.