iPhone XS Max users experience more than two times faster real-world LTE data speeds as iPhone 5s users on average in the United States, according to OpenSignal, although there are caveats to consider.
OpenSignal says it measured speeds on hundreds of thousands of iPhones across the United States from October 26, 2018 to January 24, 2019 and found that iPhone XS Max users experienced an average LTE download speed of 21.7 Mbps compared to just 10.2 Mbps for iPhone 5s users.
iPhone XS users saw an average LTE download speed of 17.6 Mbps, while iPhone 6 through iPhone 8 Plus users posted average LTE download speeds of between 15.6 Mbps and 17.1 Mbps, as measured by OpenSignal.
OpenSignal attributes the faster data speeds on newer iPhones to improved modems and antenna designs in those devices, such as 4x4 MIMO support in the iPhone XS and iPhone XS Max compared to 2x2 MIMO on older iPhones, but the results are also likely influenced by socioeconomic factors.
Someone who is still using an iPhone 5s in 2019 could be a price-conscious consumer who is unable to justify the cost of upgrading to a newer iPhone, for example, while relying on a discount carrier with inferior wireless coverage or capped data speeds compared to major carriers such as Verizon and AT&T.
That said, while the results may be somewhat skewed, a newer iPhone should be able to achieve faster data speeds than an older iPhone, assuming it's connected to a cellular tower with the latest LTE equipment.
