Here is a detailed side-by-side comparison of real-world battery tests between the iPhone 17 and the Samsung Galaxy S25 Ultra from multiple sources:
Battery Capacity and Efficiency:
- The iPhone 17 comes with a 3,692 mAh battery, slightly larger than its predecessor but still smaller compared to many competitors. It emphasizes software and hardware optimization for battery efficiency over outright battery capacity.
- The Samsung Galaxy S25 Ultra houses a 5,000 mAh battery, larger in capacity, designed to support its high-powered hardware and large display.
Battery Life Tests and Real-World Usage:
- The iPhone 17 offers excellent battery life for its size, with some tests showing it lasting about 15 hours of active use. Apple's official claim is up to 30 hours of video playback, and real-world usage often approaches full-day coverage with moderate to heavy use, sometimes leaving 20-30% battery by bedtime.
- The Samsung Galaxy S25 Ultra also delivers strong performance, offering around a day and a half of regular use on its 5,000 mAh battery. In direct comparisons under heavy load, like video streaming and gaming, the Galaxy tends to drain faster percentage-wise despite the larger battery.
Controlled Battery Drain Tests:
- In a 6-hour battery drain test running apps like Instagram continuously, the iPhone 17 Pro Max (similar battery tech to iPhone 17) retained around 38% charge remaining at the end, while the Galaxy S25 Ultra ended with approximately 20%.
- This shows the iPhone's better power efficiency despite a smaller battery, likely due to Apple's system optimizations.
- Another test showed the iPhone 17 dropped only 62% battery over 6 hours, while the Galaxy S25 Ultra lost about 80% under similar conditions.
Charging Speeds:
- The iPhone 17 supports fast charging, reaching 50% battery in roughly 20-30 minutes using a 40W or higher wired charger, with wireless charging being slower but still competitive.
- The Galaxy S25 Ultra also supports fast charging with slightly faster wired speeds at 45W, and wireless charging is rated at 15W compared to iPhone's 25W in pro models.
Battery Life in Usage Scenarios:
- Apple claims improvements in video playback times with the iPhone 17 lasting up to 30 hours, which is an 8-hour improvement over the iPhone 16.
- The Galaxy S25 Ultra's battery life is very good during mixed-use scenarios, but real-world tests under continuous load (e.g., gaming, video) reveal faster drain despite its larger battery capacity.
- The iPhone performs better with video playback and gaming efficiency, squeezing more usage time from its smaller battery.
Thermal and Stability Observations:
- During heavy usage, the Galaxy S25 Ultra runs slightly warmer (around 36°C) versus about 34°C on the iPhone 17 Pro Max.
- The iPhone also tends to maintain better performance stability under sustained load in benchmark tests.
Summary of Real-World Battery Test Outcomes:
- iPhone 17's carefully optimized integration of hardware and software enables it to deliver longer battery life relative to its battery size.
- Samsung Galaxy S25 Ultra benefits from a larger battery and faster charging but may have shorter endurance in continuous use scenarios.
- Both phones provide competitive battery life and charging experiences, with the iPhone 17 showing superior efficiency and endurance in extended tests.