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The short answer: For most people, the LG C4 is the safer, more versatile choice due to its superior gaming features (4 HDMI 2.1 ports, Dolby Vision, and lower input lag) and better overall smart TV platform. The Samsung S90D offers a brighter panel and punchier colors, which can be great for bright rooms or HDR content, but it lacks Dolby Vision and has fewer HDMI 2.1 ports. Ultimately, your choice depends on your priorities: LG C4 for gaming and compatibility, Samsung S90D for brightness and color pop.
LG C4 uses a WOLED panel with a brightness booster. It gets noticeably bright, especially in HDR, but generally not as bright as the Samsung S90D, which uses a QD-OLED panel. The S90D’s quantum dot layer delivers higher peak brightness in small highlights and more saturated, vibrant colors, especially in bright scenes. In a dark room, both look stunning, but the S90D tends to show deeper blacks and less color washout in very bright highlights. However, the LG C4 has better near-black handling and less color fringing in some test patterns, which some viewers find more natural. For SDR content, both are excellent, but the S90D’s extra brightness can make it look punchier in a well-lit room.
Both TVs support 120Hz refresh rates, VRR (Variable Refresh Rate), ALLM (Auto Low Latency Mode), and low input lag. However, there are critical differences. The LG C4 has four full-bandwidth HDMI 2.1 ports, so you can connect a PS5, Xbox Series X, gaming PC, and soundbar all at full speed. The Samsung S90D has only four HDMI ports as well, but only two or three are HDMI 2.1 (depending on region and model), so you might have to sacrifice a 4K/120Hz device. Also, the LG C4 supports Dolby Vision gaming at 120Hz, while the S90D only supports HDR10+ gaming, which is less common. If you own an Xbox or a movie collection in Dolby Vision, the LG is a clear winner. Additionally, LG’s game optimizer dashboard is more user-friendly, offering specific features like a crosshair, and it has a lower input lag in some tests (though both are under 10ms, imperceptible in practice).
The LG C4 runs on webOS, which is intuitive, fast, and has excellent app support. It also includes a Magic Remote with pointer control, which many find superior for navigating streaming apps. Samsung uses Tizen, which is also quick and has all major apps, but the interface is cluttered with ads and some find it less smooth. Both support voice assistants: LG has ThinQ with Google Assistant and Alexa built-in, while Samsung has Bixby and works with Alexa and Google Assistant. For most users, webOS feels more polished and user-centric, but if you’re in the Samsung ecosystem (e.g., Samsung phone), Tizen might sync better. Remember to consider the ecosystem you already use.
Both TVs feature sleek, ultra-thin panels. The LG C4 has a central stand that is fairly stable, but the Samsung S90D has a flat, wide stand that might be easier to fit on narrow furniture. In terms of ports, we touched on it: LG has four HDMI 2.1, while Samsung has a mix. Also, check for optical audio, USB, and analog outputs, which both have. The LG C4 supports Wi-Fi 6E and Bluetooth 5.2, while the S90D has Wi-Fi 6 and Bluetooth 5.2. For wall mounting, both are VESA compatible, but the LG’s slim design leaves less room for cables behind the TV.
Generally, the LG C4 launches at a similar price to the S90D, but the LG tends to drop in price faster over time. Given that the C4 offers Dolby Vision, more HDMI 2.1 ports, and a more mature OS, it often represents better value for the money. However, if you find the S90D on a significant discount, its superior brightness might make it worth the trade-off. It’s always wise to check current prices on sites like our recommended TV buying guide for updated deals and comparisons.
Both TVs have decent built-in speakers, but neither will replace a soundbar. The LG C4 has a 40W speaker system with support for Dolby Atmos (virtual), while the Samsung S90D has 40W as well, but with Object Tracking Sound that slightly simulates movement. LG also includes a feature called AI Sound Pro that upmixes stereo to virtual 9.1.2 surround, which can be impressive. For gaming, both support HGiG. In terms of other features, LG includes a webOS that can be tailored to your habits, while Samsung has a SolarCell remote (never needs batteries) which is a nice touch.
The Samsung S90D’s higher brightness and anti-glare coating make it slightly better in bright rooms with direct light. The LG C4 is still very good, but if you have lots of windows, the S90D will maintain better contrast.
No, Samsung refuses to support Dolby Vision and instead uses HDR10+ which is supported by some streaming services and Amazon Prime. If you watch a lot of Dolby Vision content on Netflix or Disney+, the LG C4 is the way to go.
Yes, if you have a model with at least two HDMI 2.1 ports. Most S90D sizes have 4 HDMI ports, but only 2 are 2.1 in some sizes (like the 55-inch). Check the spec sheet carefully. The LG C4 has all four as 2.1, so no worries.
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