Unveiled on 24 February 2014 at Mobile World Congress in Barcelona, Spain, it was released on 11 April 2014 in 150 countries as the immediate successor to the Galaxy S4.

[10] However, the S5 was criticized for bloatware, its unresponsive fingerprint scanner, and its ostensibly non-"premium" polycarbonate in light of rival smartphones' metal or glass bodies.

The Galaxy S5 was unveiled on 24 February 2014 as part of the company's presentation at Mobile World Congress in Barcelona, Spain.

Samsung Electronics president JK Shin explained that consumers did not want a phone dependent on "eye-popping" or "complex" technology, but one with "beautiful design and performance", a "simple, yet powerful camera", "faster and seamless connectivity", and fitness-oriented features.

It features a rounded, polycarbonate chassis carrying a "modern glam" look with a dot pattern similarly to that on the 2012 Google Nexus 7 tablet computer, faux metal trim and a removable rear cover.

Unlike past models, the S5's rear cover uses a higher quality soft plastic and is dimpled to improve grip.

The S5's screen is a 5.1-inch (130 mm) 1080p Super AMOLED panel, which is slightly larger than that of the S4, and allows for automatic brightness and gamut adjustments.

[25] The front camera uses a Samsung CMOS S5K8B1YX03 image sensor, an aperture of f/2.4 and captures both photos and videos at 1080p; the latter at 30 frames per second.

The IR blaster is a transmitter only and it has a built-in database of devices that can be controlled by Samsung's Smart Remote application.

It is Qi compatible (requires an optional Wireless Charging Cover) and also contains an "Ultra Power Saving" mode to extend further battery life; when enabled, all non-essential processes are disabled, and the screen switches to grey scale rendering.

Samsung claims that with Ultra Power Saving on, an S5 with 10% charge remaining can last for an additional 24 hours in standby mode.

Certain aspects of the changes were influenced by a recent patent licensing deal with Google, which requires that Samsung's TouchWiz interface follow the design of "stock" Android more closely.

The S5 adds the Galaxy Note 3's "My Magazine" feature to the leftmost page on the home screen, the Settings menu was updated with a new grid-based layout, a Kids' Mode was added, while the S Health app was given expanded functionality, integrating with the new heart rate sensor on the device, along with the new Gear 2 smartwatch and Gear Fit activity tracker.

Due to carrier policies, Download Booster was not available on Galaxy S5 models released in the United States running KitKat 4.4.2, excluding T-Mobile US and U.S.

The "Quick Glance" feature from the Galaxy S4 was succeeded by "Air wake-up", where hovering above the front proximity sensor next to the "Samsung" wordmark wakes the phone up from stand-by mode rather than just showing the clock and status.

[52] The S5 also adds "Private Mode", which allows users to maintain hidden apps and file folders that cannot be accessed without additional authentication.

[19][20] The camera app was updated with a new "Shot & More" menu that captures eight still photos in quick succession stored into a single JPG file[how?

[58] It enables new features such as "Google Now on Tap", which allows users to perform searches within the context of information currently being displayed on-screen, and "Doze", which optimizes battery usage when the device is not being physically handled.

The S5 Neo is a lower cost variant of the original Galaxy S5 that downgrades the SoC to an Exynos 7580 Octa system-on-chip, while improving the front camera to a 5-megapixel unit.

The display of the S5 was praised for having a high quality, not being as oversaturated as previous models, and having a wide range of viewing angles, brightness states, and gamut settings to fine tune its appearance.

TechRadar also noticed that, despite the high power of its processor, some apps and interface functions suffered from performance issues, indicating that the S5's operating system may not have been completely optimized for its system-on-chip.

While the S5's camera interface was praised for having a streamlined design, it was criticized for taking too long to load, and the Selective Focus features were panned for being inconsistent in quality.

[7][8] While praised for providing more uses than the Touch ID function on the iPhone 5s, the fingerprint sensor was panned for requiring an unnatural vertical swiping gesture, having inconsistent and unforgiving results, and for being inconvenient in comparison to a password or PIN in most use cases due to these shortcomings.

[7][8] The Berlin-based Security Research Labs found that because the S5's fingerprint sensor could easily be spoofed, allows unlimited chances and does not require a PIN after 48 hours of inactivity or on startup like Touch ID, and can be used for more than just unlocking the phone, it "gives a would-be attacked [sic] an even greater incentive to learn the simple skill of spoofing fingerprints.