The biggest differences between the iPhone 6 and the iPhone 6 Plus are their size and battery life. The iPhone 6 Plus display is an enormous 5.5" diagonally, while the iPhone 6 is 4.7". Both are larger than the 4" iPhone 5s display.
The larger display allows the iPhone 6 Plus to fit in more pixels (1920 x 1080) compared with the iPhone 6 (1334 x 750). It also allowed Apple to fit a larger battery in the iPhone 6 Plus, which lasts longer — video playback of 14 hours and audio playback of 80 hours, compared with 11 hours and 50 hours respectively for the iPhone 6.
The phones have the same operating system, processor and chip, camera and video recording capabilities. Both phones support Apple Pay. Both are available in 16GB, 32GB and 128GB models. The iPhone 6 is $100 cheaper than the iPhone 6.
For a good comparison of iPhone models, see this page on Apple's website.
Comparison chart
 | iPhone 6 | iPhone 6 Plus |
|---|---|---|
| Weight | 129 g (4.55 oz) | 6.07 ounces (172 grams) |
| Display | Retina HD display 4.7-inch (diagonal) LED-backlit widescreen Multi‑Touch display with IPS technology 1334-by-750-pixel resolution at 326 ppi 1400:1 contrast ratio (typical) 500 cd/m2 max brightness (typical) Full sRGB standard | 5.5" |
| Dimensions | 138.1 mm (5.44 in) H, 67.0 mm (2.64 in) W, 6.9 mm (0.27 in) D | 158.1 mm (6.22 in) H, 77.8 mm (3.06 in) W, 7.1 mm (0.28 in) D |
| Rear camera | 8-megapixel iSight camera with 1.5µ pixels, Autofocus with Focus Pixels ƒ/2.2 aperture, True Tone flash, Five-element lens, Hybrid IR filter, Backside illumination sensor, Sapphire crystal lens cover | 8 MP, Flash |
| Price | $650 (16GB), $750 (64GB), $850 (128GB) | $750 (16GB), $850 (64GB), $950 (128GB) |
| Front camera | 1.2-megapixel photos, ƒ/2.2 aperture, 720p HD video recording, Backside illumination sensor | 1.2 MP |
| CPU | Dual-core 1.4 GHz (Apple A8) | Dual-core 1.4 GHz (Apple A8) |
| Removable storage | None | Not available |
| Fingerprint reader | Yes | Yes |
| Colors available | Gold, silver, space gray | Gold, silver, space gray |
| Manufacturer | Apple Inc. | Apple Inc. |
| Website | apple.com/iphone-6 | http://www.apple.com/iphone |
| Memory card slot | None | No |
| Virtual Assistant | Siri | Siri |
| Headphone Jack (3.5mm) | Yes | Yes |
| Storage capacity | 16 GB, 64 GB and 128 GB | 16 GB, 64 GB and 128 GB |
| Removable Battery | No | No |
| Compatible networks | GSM, CDMA, EVDO, HSPA+, LTE | GSM, CDMA, 3G, EVDO, HSPA+, LTE |
| Screen Resolution | 1334 x 750 pixels | 1920 x 1080 pixels |
| Screen Resolution Density | 326 ppi | 401 ppi (pixels per inch) |
| Battery life | Built-in rechargeable lithium-ion battery, Charging via USB to computer system or power adapter, Talk time: Up to 14 hours on 3G, Internet use: Up to 10 hours on 3G, up to 10 hours on LTE, up to 11 hours on Wi‑Fi | Talk time: 14 hours on 3G; Standby time: 10 days; Internet use: 10 hours on 3G/LTE, 11 on Wi-Fi; Video playback: 14 hours; Audio playback: 80 hours |
| Memory | 1 GB RAM | 1 GB RAM |
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