A new battery life test from PhoneBuff reveals that iPhone 17 Pro Max devices consume significantly more power when using 5G compared to WiFi. In a controlled benchmark simulating everyday activities like texting, web browsing, streaming, Instagram, and FaceTime, the iPhone on 5G lasted 10 hours and 22 minutes of screen-on time, while the WiFi version retained 25% battery when the 5G model died.

This 3-hour difference between cellular and WiFi connectivity is smaller than many expected, highlighting the power efficiency of modern iPhones even on cellular networks. The test maintained both devices in a static location with stable signal strength, which likely contributed to the narrower gap. Results would vary significantly based on location, signal strength, and user activities.

PhoneBuff notes that switching between cell towers while moving would likely increase power consumption substantially, as this operation is particularly intensive. The test used the latest-generation Qualcomm modems found in Apple's flagship Pro models. The results provide valuable real-world data for consumers weighing the battery impact of 5G connectivity, especially as Apple continues developing its own modem technology with the upcoming iPhone 18 Pro models expected to feature the second-generation Apple C2 chip.