As a result of poor iPhone sales throughout Q4 2018 in emerging markets such as China, Apple was forced to lower its revenue guidance yesterday. However, in a memo obtained by Bloomberg, CEO Tim Cook revealed that the iPhone’s popularity continues to grow in developed markets.

Boosted (presumably) by the improved iPhone trade-in program that Apple continues to promote and the multiple holiday season offers available through both retailers and carriers, Cook announced that iPhone activations set new records in both the US and Canada last week on Christmas Day. This has helped the company’s ...