Infinix has been selling budget smartphones in India for a while now, and has mainly focused on the sub-Rs. 10,000 segment. Many of of the Infinix models we have tested in the past — including the Note 5 (Review), Hot S3X (Review), and Note 5 Stylus (Review) — have fared well in our review process. The Infinix S4 is the company's newest offering, and boasts of a rear triple camera setup and a big battery. Is it better than its competitors? We review it to find out.
At first glance, it is a little hard to believe that the Infinix S4 is a sub-Rs. 10,000 smartphone. It is well designed and the glossy gradient back is the highlight of it all. The Infinix S4 is available in three colour variants, Nebula Blue, Space Gray, and Twilight Purple. We got a Nebula Blue review unit, and it was gorgeous to look at.
While the glossy back gives an impression of glass, it is made out of plastic. However, the glossy back is a fingerprint magnet and we had to keep wiping the phone from time to time. Infinix does ship a clear case in the box, which will help keep the smudges off to some extent.
The Infinix S4 sports a big display with a waterdrop notch, and the bezels aren't too thick. Our review unit had a pre-applied screen protector, and there was an extra one in the box. The earpiece on the S4 is quite slim and is wedged between the frame and the display. We found the phone to be comfortable to hold, and it wasn't too heavy.
Infinix has positioned the power and volume buttons on the right but we found the volume buttons to be slightly too high for our liking. Nonetheless, all these buttons have good clicky feedback. This SIM tray is on the left.
Turn the phone around, and the triple camera setup is sure to grab your attention. Such a setup isn't common at this price point and we were surprised to see it on the Infinix S4. The camera module protrudes slightly causing the phone to rock when placed on flat surfaces. There is a quad-LED flash right below the camera module. The fingerprint scanner is positioned next to the camera and is easy to reach. The scanner has a matte texture, breaking the monotony of the glossy back.
At the bottom, you'll find a loudspeaker grille, 3.5mm headphone jack, and Micro-USB port, while the top of the device is completely blank.
The Infinix S4 sports a 6.21-inch HD+ (720x1520 pixels) display with a 19.5:9 aspect ratio, and the company claims an 89 percent screen-to-body ratio. Infinix also says that the S4 puts out 500nits of brightness, and we found the display to be legible when outdoors. The display was crisp and were happy with the output, however, we couldn't find a way to tweak the colour temperature. There's an Eye-care feature that filters blue light to reduce eye strain.
Infinix has picked the MediaTek Helio P22 SoC to power the S4. This processor is slowly becoming common at this price point, and we have seen other smartphones including the Realme C2 (Review) and Oppo A1k (Review) using the same SoC.
The Infinix S4 comes in one configuration only, with 3GB of RAM and 32GB of storage. It has a dedicated microSD card slot that accepts cards of up to 256GB. Connectivity options on the Infinix S4 include Bluetooth 5, Wi-Fi, dual 4G VoLTE, and GPS. This phone packs in a 4000mAh battery and you get a 10W charger in the box.
Infinix ships the S4 with XOS 5.0 running on top of Android 9 Pie. This is the latest version of Android, and our unit was running the April security patch which is acceptable. There are quite a few UI customisations, and it does not look like stock Android.
It has support for themes and you can download more through the Themes app that comes preinstalled. We also found several other apps preinstalled including PHX Browser, Google apps, and Danger Dash. The PHX browser would send spammy notifications once in a while, so we uninstalled it.
There are a few useful feature additions on the Infinix S4 which help the user experience. The phone has an AIBox feature which clubs incoming notifications and shows alerts only from the apps you wish to be notified by. It also has a smart panel which can be accessed from anywhere and houses a couple of shortcuts.
Another feature called Intelligent Voice Broadcast will read out the weather and your schedule for the day once the morning alarm is switched off. It can also read out WhatsApp and Facebook updates as well. We tried this feature and it worked well, but we couldn't change the voice or the language. Gestures are also available to help you navigate through the UI by swiping on the bottom of the display.
The Infinix S4 offers good enough performance with its MediaTek Helio P22 SoC. We did not notice lag while scrolling through the menus or while switching between multiple apps. The 3GB of RAM helps the S4 retain apps in memory, which aids in multitasking. Just like the Realme C2, though, the Infinix S4 also took slightly longer than usual to load large apps.
We ran our benchmark apps which revealed how the Helio P22 performs in the Infinix S4. In AnTuTu, the S4 managed 74,474 points which is lower than what the Realme C2 scored. This phone also got 762 and 3,646 points in Geekbench 4's single-core and multi-core tests respectively. It scored 11,399 in 3DMark Ice Storm Unlimited and 8,288 in Ice Storm Extreme. The Infinix S4 also managed to score 11fps in GFXBench Manhattan 3.1 and 27fps in T-Rex.
PUBG Mobile ran at the low preset with the graphics quality set to Smooth and frame rate set to Medium. We did encounter lag while playing the game, but it wasn't as bad as on the Realme C2. The phone registered a 5 percent battery drop after 20 minutes of gameplay and did get warm to the touch around the upper rear.
We found the rear-mounted fingerprint scanner and the face recognition features to be quick to unlock the smartphone.
The Infinix S4 manages to deliver good battery life thanks to its 4000mAh battery. With our usage, which consisted of WhatsApp, using Google Maps for navigation, running our benchmarks, and taking a few camera samples, the smartphone went on for about a day and a half. In our HD video loop test, the Infinix S4 managed to clock 17 hours and 35 minutes. When the battery runs out, the supplied charger is capable of charging it to 31 percent in 30 minutes, and it takes around 2 hours to top it up completely.
The triple camera setup on the Infinix S4 is the highlight of this product, as three cameras aren't common at this price point. There's a 13-megapixel primary sensor with an f/1.8 aperture, an 8-megapixel wide-angle sensor with a 120 degree field of view, and the third camera is a 2-megapixel depth sensor. There's also a quad-LED flash just below the camera module. At the front, this phone has a 32-megapixel selfie shooter with an f/2.0 aperture and screen flash.
The camera app has AI features built in to help the smartphone detect what it is pointed towards. AI is enabled by default on the S4. There are quick toggles available for HDR and the flash, as well as a button to switch to the wide-angle sensor. The Camera app also has other modes such as Beauty, Bokeh, Video, and AR Shot.
Photos taken with the Infinix S4 in daylight were good. The phone managed to lock focus quickly and get the exposure right. It also managed good amounts of detail when shooting outdoors. Macros were sharp and the S4 did manage to surprise us with its photo quality. The phone also managed good separation between the subject and the background.
The Infinix S4 lets you select the level of blur when taking portrait shots but we found the edge detection quality to below average. Low-light is where the camera takes a beating. Shots weren't sharp and had huge grain in the output. The wide-angle lens let you take wider landscapes but we noticed barrel distortion in the output.
Selfies were good and the presence of HDR does help when shooting outdoors. There is face detection as well, which helps get the exposure right before taking a shot. Video recording maxes out at 1080p for the cameras and there is no stabilisation, resulting in shaky output.
The Infinix S4 is one of very few smartphones priced below Rs. 10,000 to sport a triple camera setup. Its wide-angle sensor is handy when shooting landscapes, and the primary sensor does manage good photos in daylight. Sadly camera performance takes a dip in low light. While the MediaTek Helio P22 SoC isn't the most powerful processor in this price bracket, it does manage to deliver a usable experience.
At its asking price of Rs. 8,999, the Infinix S4 commands a slight premium over the Realme C2 (Review) but it sports a fingerprint sensor and has slightly better cameras. If that is good enough for you, go for the Infinix S4, but if you want more value for your money, the Redmi 7 (Review) is a solid alternative.