Infinix Smart 4 vs Redmi K90 Ultra

The Infinix Smart 4 (2019) runs on the MediaTek Helio A22, while the Redmi K90 Ultra (2026) runs on the Qualcomm Snapdragon 8 Elite. By overall MobileRank rating, the Redmi K90 Ultra leads — 73/100 vs 20/100 (a 53-point difference). Key differences: the Redmi K90 Ultra has the bigger battery (8550 mAh vs 4000); the main camera is 8 MP vs 50 MP; the Redmi K90 Ultra is faster in AnTuTu (3,233,695 vs 155,362); the Redmi K90 Ultra has NFC for contactless payments, the Infinix Smart 4 doesn't; the Infinix Smart 4 is noticeably lighter (183g vs 227g).

The Redmi K90 Ultra significantly outperforms the Infinix Smart 4 by 53 points (73/100 vs 20/100).
Profile comparison
Category scores
Infinix Smart 4
Performance 10
Display 38
Camera 10
Battery 32
Portability 66
Value for money
Redmi K90 Ultra
Performance 92
Display 94
Camera 37
Battery 78
Portability 40
Value for money 82
What makes Infinix Smart 4 better?
  • Lighter: 183g vs 227g

  • Better portability (66/100 vs 40/100)
What makes Redmi K90 Ultra better?
  • Higher AnTuTu: 3233695 vs 155362
  • Better Geekbench Single: 3041 vs 300
  • Better Geekbench Multi: 9494 vs 486
  • Bigger battery: 8550 vs 4000 mAh
  • Better main camera: 50MP vs 8MP

  • Higher performance (92/100 vs 10/100)
  • Better camera (37/100 vs 10/100)
  • Longer battery life (78/100 vs 32/100)
  • Better display (94/100 vs 38/100)
Comparison verdict

Comparing the Infinix Smart 4 vs the Redmi K90 Ultra, the Redmi K90 Ultra scores 53 points higher (73/100 vs 20/100). In the "performance" category, the Redmi K90 Ultra leads (92/100 vs 10/100). In the "camera" category, the Redmi K90 Ultra leads (37/100 vs 10/100). In the "battery" category, the Redmi K90 Ultra leads (78/100 vs 32/100). In the "performance" category, the Redmi K90 Ultra significantly outperforms the Infinix Smart 4 (92/100 vs 10/100). In the "display" category, the Redmi K90 Ultra significantly outperforms the Infinix Smart 4 (94/100 vs 38/100). In the "camera" category, the Redmi K90 Ultra notably outperforms the Infinix Smart 4 (37/100 vs 10/100). In the "battery" category, the Redmi K90 Ultra significantly outperforms the Infinix Smart 4 (78/100 vs 32/100). In the "portability" category, the Infinix Smart 4 notably outperforms the Redmi K90 Ultra (66/100 vs 40/100).

Infinix Smart 4: The Infinix Smart 4 is a better fit for everyday use.
Redmi K90 Ultra: The Redmi K90 Ultra is a better fit for gamers and power users, those who care about battery life, budget-conscious buyers.
Specs comparison
Specification Infinix Smart 4 Redmi K90 Ultra
Processor MediaTek Helio A22 Qualcomm Snapdragon 8 Elite
AnTuTu 155362 3233695
Geekbench Single 300 3041
Geekbench Multi 486 9494
Display 6.6" IPS LCD 6.8" AMOLED
Resolution 720x1600 1280x2772
Refresh rate 165 Hz
Battery 4000 mAh 8550 mAh
Charging 100W
Main camera 8 MP 50 MP
Ultrawide 0 MP 8 MP
Front camera 5 MP 20 MP
RAM 1GB 12GB / 16GB
Storage 256GB / 512GB
OS Android 9.0 Pie (Go edition) Android 16
Brightness (peak) 3500 nits
NFC no yes
Protection IP68/IP69
Dimensions 167.0×76.0×8.3 mm 162.9×77.9×8.2 mm
Weight 183 g 227 g
Launch price $420
Camera comparison
Infinix Smart 4
  • Main: 8MP
  • Front: 5MP
10
camera
Redmi K90 Ultra
  • Main: 50MP f/1.7
  • Ultrawide: 8MP
  • Front: 20MP
37
camera
Display comparison
Infinix Smart 4
  • 6.6" IPS LCD
  • Resolution: 720x1600
  • Refresh rate: —
38
display
Redmi K90 Ultra
  • 6.8" AMOLED
  • Resolution: 1280x2772
  • Refresh rate: 165 Hz
94
display
Battery and charging
Infinix Smart 4
  • 4000 mAh
  • Wireless charging: no data
32
battery
Redmi K90 Ultra
  • 8550 mAh
  • Wired: 100W
  • No wireless charging
78
battery
Overall performance score

We compared Infinix Smart 4 and Redmi K90 Ultra, covering their specs and all relevant benchmarks.

Infinix Smart 4 MediaTek Helio A22
20/100
155362 AnTuTu
Redmi K90 Ultra Qualcomm Snapdragon 8 Elite
73/100 +95.2%
3233695 AnTuTu

Redmi K90 Ultra leads Infinix Smart 4 by 95.2% in our overall performance rating.

Benchmarks
Launch prices and where to check today's
Infinix Smart 4
Price unknown
Redmi K90 Ultra
$420
Detailed category analysis
performance

In the "performance" category, the Redmi K90 Ultra significantly outperforms the Infinix Smart 4 (92/100 vs 10/100).

display

In the "display" category, the Redmi K90 Ultra significantly outperforms the Infinix Smart 4 (94/100 vs 38/100).

camera

In the "camera" category, the Redmi K90 Ultra notably outperforms the Infinix Smart 4 (37/100 vs 10/100).

battery

In the "battery" category, the Redmi K90 Ultra significantly outperforms the Infinix Smart 4 (78/100 vs 32/100).

portability

In the "portability" category, the Infinix Smart 4 notably outperforms the Redmi K90 Ultra (66/100 vs 40/100).

Frequently asked questions
Which is better: the Infinix Smart 4 or the Redmi K90 Ultra?

The Redmi K90 Ultra significantly outperforms the Infinix Smart 4 by 53 points (73/100 vs 20/100).

What is the rating of the Infinix Smart 4 and the Redmi K90 Ultra?

The Infinix Smart 4 has a MobileRank rating of 20/100, the Redmi K90 Ultra — 73/100.

Which has the better camera: the Infinix Smart 4 or the Redmi K90 Ultra?

The Redmi K90 Ultra leads on camera score (37/100 vs 10/100).

Which is more powerful: the Infinix Smart 4 or the Redmi K90 Ultra?

The Redmi K90 Ultra leads on performance (92/100 vs 10/100).

Should you choose the Infinix Smart 4 over the Redmi K90 Ultra?

The Infinix Smart 4 is a better fit for everyday use. The Redmi K90 Ultra is a better fit for gamers and power users, those who care about battery life, budget-conscious buyers.