Am here to help you make tell you the difference between iPhone 6 and Galaxy S5
OS: The iPhone 6 uses iOS (8.x) while the Samsung Galaxy S5 runs on Android 4.4.2 KitKat upgradeable to Android v5.0 Lollipop and has TouchWiz UI.
DIMENSIONS: The iPhone 6 has a dimension of 5.44 x 2.64 x 0.27 inches while its competitor the S5 has a dimension of 5.59 x 2.85 x 0.32 inches.
WEIGHT: iPhone 6 weighs 4.55 Oz while the Galaxy S5 weighs 5.11 Oz, it’s obvious that the Samsung smartphone weighs more than the iPhone 6.
RUGGEDNESS: The iPhone 6 does not have the capability to resist water or dust whereas the Galaxy device is water resistant and dust resistant.
SIZE: The iPhone 6 is actually 4.7 inches while the S5 is blessed with a 5.1 inch screen. The difference in screen is not actually much. The iPhone smartphone, has a screen resolution of 750 x 1334 pixels, while the Galaxy S5 has a resolution of 1080 x 1920 pixels. The pixel density of the iPhone 6 is a 326 ppi while that of the S5 is 432 ppi.
SCREEN DISPLAY: The iPhone 6 uses an IPS LCD kind of screen while that of the Samsung Galaxy is super AMOLED.
CAMERA: The iPhone 6 has a rear camera quality of 8 megapixels and a front camera quality of 1.2 megapixels while the S5 uses a 16 megapixels rear camera and a 2.1 front camera quality.
FLASH: The iPhone 6 uses Dual LED flash while the galaxy s5 uses LED flash.
EXTRA FEATURES: The Galaxy S5 and the iPhone 6 both have video calling, autofocus, video sharing and face detection.
BATTERY CAPACITY: The iPhone 6 has a battery capacity of 1810 mAh, while the S5 comes with a 2800 mAh battery.
After all said and done, if you ask me for my overall opinion, I will say the Samsung Galaxy S5 is a better device.