Samsung Galaxy

Background
Samsung Galaxy is a series of smartphones and tablets that are designed, manufactured and marketed by Samsung Electronics. The series includes the Samsung Galaxy S series of flagship smartphones, the Samsung Galaxy Tab series of tablets, the foldable Samsung Galaxy Z series, and the Samsung Galaxy Watch series of smartwatches. They also made the Samsung Galaxy A series, the Samsung Galaxy F series, the Samsung Galaxy M series, and the discontinued Samsung Galaxy J series.

1st Logo (June 4, 2010-May 2, 2011)
Logo: On a black background, we see multiple cubes forming a stylized S. After that, the text "GALAXY S" or "Samsung GALAXY S II" appear below.

Technique: Impressive computer animation for a boot screen.

Music/Sounds:
 * Samsung Galaxy S: A calm theme.
 * Samsung Galaxy S II: A synth rendition of the Samsung Galaxy's signature theme, "Over the Horizon", originally composed by Joong-sam Yun

Availability: Only seen when booting up a Samsung Galaxy S and Samsung Galaxy S II, respectively. However, Samsung Galaxy S II's running Android Jelly Bean use the next logo instead.

Legacy: This logo marks the debut of Samsung Galaxy's signature theme, "Over the Horizon".

2nd Logo (May 29, 2012-April 27, 2013)
Logo:
 * Startup: On a black background, a blue light spins around and forms an angled oval. The Samsung wordmark then fades inside the trajectory of the light, after which it then dims out. The wordmark glows in cyan.
 * Shutdown: The blue light immediately draws the oval, the Samsung wordmark fades in, and the whole logo fades.

Technique: The light and the glow. Somewhat simplistic.

Music/Sounds:
 * Galaxy S3 and related phones:
 * Startup: A high, echoing pindrop sound, followed by the trademark 5-note Galaxy theme.
 * Shutdown: Just the last three notes of "Over the Horizon" played on piano, together with a whoosh sound.
 * Galaxy S4 and related phones:
 * Startup: A soothing orchestra/piano rendition of "Over the Horizon". Taken from said phone's rendition of the ringtone, arranged by Jamie Christopherson
 * Shutdown: A short warbling sounder.

Music/Sounds Trivia: The pindrop sound on the S3 version of the startup sound originates from a segment of the S II version of the "Over the Horizon" ringtone.

Music/Sounds Variants: On Galaxy S3's running Android 4.2 Jelly Bean, the Galaxy S4 startup sound is used.

Availability: It can be seen when booting up a Galaxy S3, Galaxy S4 and other Galaxy devices released around the time period running Android Jelly Bean or Android KitKat. However, Galaxy S4's running Android Lollipop use the next logo instead, albeit retaining the audio from this logo.

3rd Logo (April 11, 2014-August 21, 2015)
Logo:
 * Startup: The Samsung wordmark draws itself in, first in blue and pink, followed by white, as it zooms in. A thin outline of the angled oval in the Samsung corporate logo is briefly drawn in and seen.
 * Shutdown: The animation of the startup logo plays faster and in reverse.

Technique: The text drawing itself in. This is rather simplistic compared to the previous logo.

Music/Sounds:
 * Galaxy S5 and related phones:
 * Startup: A remix of the Galaxy trademark theme
 * Shutdown: The startup music is cut down to the last two notes. On some devices, it is silent.
 * Galaxy S6 and related phones:
 * Startup: A 4-note synth theme.
 * Shutdown: None.

Music/Sounds Variants: Samsung Galaxy S4's running Android Lollipop retain their same startup and shutdown audio from the last logo.

Availability: Seen when booting up a Galaxy S5, Galaxy S6, and other devices released during the time period. Also seen on Samsung Galaxy S4 devices running Android Lollipop. In most cases, this logo is replaced with the next logo upon updating to Android Marshmallow.

4th Logo (March 11, 2016-March 16, 2018)
Logo:
 * Startup:
 * Samsung Galaxy S7: A thin outline of the S/\MSUNG wordmark draws itself in, followed by being filled in white via the same drawing animation. The logo zooms in slowly.
 * Samsung Galaxy S8 and S9: Similar to above, but the outline of the SAMSUNG wordmark draws itself in fully before the whole wordmark turns white via a cross-fade. Also, there is no zoom-in.
 * Shutdown: In both cases, the animation plays in reverse.

Technique: Similar to the previous logo, but it's even more simplistic.

Music/Sounds: None.

Availability: Seen when booting up a Samsung Galaxy S7 and other Samsung Galaxy devices released during the time, such as the ill-fated Samsung Galaxy Note 7. It is also seen on the Samsung Galaxy S8 and Galaxy S9, but only on versions of Android prior to Android Pie 9.0.

Logo (March 4, 2019-)
Logo: It's only the still Samsung logo, in white, on a black background. It then either cuts to the lock screen (when starting up) or fades out (when shutting down).

Variant: On newer phone models starting from 2021, the Samsung logo appears first, then the word "Galaxy", the text "Secured by Knox" and the Powered by Android logo appear below. Then after some time, everything but the "Samsung Galaxy" text disappears. This is only seen when booting up the smartphone, but the shutdown logo remains the same. The phone model name is no longer shown before the boot animation, unlike the previous boot screens.

Technique: None.

Music/Sounds: None.

Availability: Current. Seen on the Samsung Galaxy S10 and every Galaxy smartphone released by Samsung since then. It may also be seen on older devices running newer versions of Android starting from Android Pie 9.0.