6 vs 15 Ultra

Phone 1

Phone 2

Winner

Fairphone 6

Lifespan decides this one: the 6 is supported until Jun 2033 at $10.67 per month of safe use, while the 15 Ultra runs out in Mar 2030 ($30.36/month). On a which-lasts-longer question, that's not a tie — it's the whole answer.

Value Score: 6 66 · 15 Ultra 65 — methodology

The lifespan decider

When specs are close, support length decides it — this is what each phone costs per month of safe use.

Fairphone 6 $899

Safe to buy$10.67/mo

2025◆ Buy-by Jun 20312033

Xiaomi 15 Ultra $1350

Safe to buy$30.36/mo

2025◆ Buy-by Mar 20282030

Category by category

Display

6 8015 Ultra 100

The 15 Ultra's screen is the better one — 6.73-inch 2k (1440×3200) ltpo amoled, 1–120hz, up to 3200 nits peak.

Performance

6 6415 Ultra 98

The 15 Ultra's Qualcomm Snapdragon 8 Elite (3nm) is simply the faster chip.

Camera

6 6715 Ultra 96

The 15 Ultra has the stronger camera system (4 real rear lenses vs 2).

Battery

6 6815 Ultra 88

5,410mAh vs 4,415mAh — the 15 Ultra lasts longer between charges.

Software longevity

6 10015 Ultra 53

The 6 is supported until Jun 2033 — 40 months longer than the 15 Ultra.

Value

6 6615 Ultra 65

Pound for pound, these two are equally good deals.

Full spec table

Spec	6	15 Ultra
Price (street)	$899	$1350
Display	6.31-inch LTPO OLED, FHD+, 10-120Hz adaptive	6.73-inch 2K (1440×3200) LTPO AMOLED, 1–120Hz, up to 3200 nits peak
Chipset	Qualcomm Snapdragon 7s Gen 3 (4nm)	Qualcomm Snapdragon 8 Elite (3nm)
RAM	8GB	16GB
Storage	256GB	512GB/1TB
Battery	4,415 mAh	5,410 mAh
Charging	30W wired; user-removable battery	90W wired, 80W wireless
Rear cameras	50MP main, 13MP ultra-wide	50MP main, 50MP ultra-wide, 50MP telephoto (70mm floating), 200MP periscope telephoto
Dimensions	156.5 × 73.3 × 9.6 mm	161.3 × 75.3 × 9.35 mm
Weight	193 g	226 g
Water resistance	IP55 (also MIL-STD-810H, 1.5m drop)	IP68
Supported until	Jun 2033	Mar 2030

6 full verdict →15 Ultra full verdict →Longevity master board →

Scores and verdicts are computed from our verified database — see exactly how. Specs from manufacturer documentation; prices reflect major US retailers.