Update 2.1

Update 2.1 will be the 11th major update for Geometry Dash and will most likely be released in March of 2016.

Timeline

 * May 26th, 2015: Robert Topala makes his first mention of Update 2.1 on TouchArcade, saying "I wanted to mix up the art style a bit, keep things fresh. More craziness in 2.1!". Because of this statement, it is assumed that there will be new decorations.
 * September 22nd, 2015: Topala entered Zobros' stream on twitch.tv and set up a Q&A. It is confirmed that a new jump ring will be added, as well as a new anti-cheat system that allows the game to take progress (stars) from the player's stats when they use hacks.
 * September 30th, 2015: Topala posts the first teaser for the update. The image shows a new four-legged gamemode, resembling a spider There are many speculations on what this might be, but there are no confirmations on what the new form is.
 * October 29th, 2015: Topala posts the second 2.1 WIP picture on Twitter. This image shows two new icons for the cube and a new block resembling stone and lava. The first icon appears to have 3 colours: primary gray, secondary red, and an orange glow, suggesting that you will be able to customize your glow color. The second icon seems to be leaving the default trail and it looks like it's a different from its primary and secondary colours. This is most likely a new background color trail option.
 * November 9th, 2015: Topala replied to a question that there won't be a demon level in 2.1. He also says he will try to release 2.1 before the year ends.
 * November 13th, 2015: Topala entered dak2014's stream on Twitch and made a Q&A. He said that a "secret project" (later revealed to be Geometry Dash Meltdown) would come out before 2.1 and he hoped that they would both come out before Christmas. He also mentioned that 2.1 wouldn't be too big. Additionally, he stated that the new features of 2.1 will be a new gamemode, a new gameplay ring. (presumably a new kind of jump orb, as stated in his Q&A on September 22nd), a new level (not of demon difficulty) with new music by a new composer, bugfixes, and small extra features.
 * December 1st, 2015: Topala stated on a Twitch user's chat that the new secret project (Geometry Dash Meltdown) will contain icons transferable to Geometry Dash by the press of a button, however Geometry Dash-exclusive icons can't be transferred to the new app.
 * December 11th, 2015: On TouchArcade, Topala stated that Update 2.1 will be pushed back to January 2016 as he is still fixing things such as new triggers, bugs, etc. But he has announced that Geometry Dash Meltdown will be released on December 19, 2015.
 * December 16th, 2015: In Cyclic's Twitch stream, Topala confirmed that the 2.1 song teaser would be released after Geometry Dash Meltdown comes out.
 * December 21st, 2015: 2.1 is added to Geometry Dash Lite on Google Play, with a new level xStep.
 * January 2nd, 2016: Topala posts the third 2.1 teaser on Twitter and Facebook, which hints the soundtrack for the new level. It depicts a grey and white Mario, followed by a plus sign, and then a grey and white Donkey Kong on the left. On the right, there is also a pointed finger, then another plus sign, followed by a radioactive symbol. The most likely song from this hint is MDK - Fingerbang, having Mario as M and Donkey Kong as DK.
 * January 4th, 2016: Topala entered Xenonetix's stream on Twitch, saying that 2.1 should be released in early February 2016. He also adds that new map packs and animated enemies will be added to the game in 2.1. He talks about some new things coming in a future update, like the scale trigger and the collab system, and the new rotate trigger and how it can spin an object around an axis.
 * January 5th, 2016: 2.1 is added to Geometry Dash Lite on iOS, adding a new level, xStep, and some achievements.
 * January 27th, 2016: Topala says on Toucharcade that there's going to be a new vault. He also said that there will be two types of rotation for the rotation trigger: To spin around axis or to spin around the target.
 * February 2nd, 2016: Topala said that a sneak peek for the new level will be released very shortly and announced that Update 2.1 is close to being released. He wants to make sure he fixes bugs, tweaks and hacks etc. before releasing 2.1.
 * February 4th, 2016: Topala posts the fourth 2.1 teaser on Twitter, Facebook and TouchArcade, and says that the 2.1 level sneak peek is almost ready. The image showcases a bat/dragon-like monster (which could possibly be new "monsters", and be a threat to the player) a new background, a new waterfall decoration, new stone blocks and a new blue diamond decoration, which could have some gameplay function. He also apologized on Facebook for being a bit slow.
 * February 9th, 2016: On Krazyman50's stream on Twitch, Topala provides a link to a picture of the 2.1 level editor. The picture displays a new interface for selecting colors, using three bars for hue, darkness, and brightness of the color. He also mentions possibility for a new rating system, where each level is rated on 1 to 10 out of different categories. He stated: "In a new rating system you would have rating scores for different areas. So 1-10 for visual, 1-10 for gameplay etc." He also confirmed that the new blue diamond shown in the last teaser will have some gameplay function and will not be just a decoration.
 * February 16th, 2016: Topala says that 2.1 may be delayed until March due to minor fixes and tweaks. He also said the sneak peak will be released soon.
 * February 21st, 2016: Topala uploads a video on his YouTube account, which shows off more new features from this update. The first of many features depicts rotating fireballs around a block, confirming that there will be a rotation trigger in 2.1. Then there is the bat/dragon-like monster, which is animated and it is shooting a fireball from its mouth in a horizontal position. After that is an animated waterfall, followed by an invisible outline of a square. Next is another bat/dragon-like monster, which is animated and is seen shooting a fireball from its mouth in a diagonal direction. A new dark purple-colored portal is seen next, which is likely the portal for the new gamemode, a new ground and a new background are also noticeable, and new rock decorations as well as particle decorations that are scattered throughout the level, hinting at a new particle editor (something that Topala mentioned previously). Finally, an image of what likely could be the new vault appears. The new music that could be for the new vault plays throughout the whole video, and is not the level's song, which is proved by to the music continuing after the gameplay.
 * February 28th, 2016: During Xaro's Twitch Stream, Topala confirmed that there will be exactly 3 new jump rings in 2.1. two are for gameplay and the third one is a custom orb. He also explains that orbs like "kill orbs" will be possible, as the custom orb works like a trigger.
 * March 4th, 2016: During GDSkitten's stream on Twitch, Topala shares more insight on what 2.1 will bring, sharing how you can control the animation of some monsters, and tells about a possible "touch", and "count" trigger. He also mentions a possible collision trigger, saying that the player could shoot objects, but probably won't be possible for 2.1, maybe 2.2. He finally says that Geometry Dash Meltdown will be updated after 2.1 with a new level, and a new collaboration system could be implemented after that as well.

Trivia

 * The icons that are featured in the second sneak peek picture are only 2 of the many icons that can be unlocked in Geometry Dash Meltdown. This is related to an upcoming feature in which Meltdown icons can be synced to the full version with a player's account.
 * Update 2.1 currently has the longest amount of time between two update teasers. The time between the second 2.1 WIP image (October 29th 2015) and the 2.1 song hint (January 2nd 2016) was over two months.
 * This might be due to the release of the "secret project (i.e. Geometry Dash Meltdown)", released between these two dates (December 19th, 2015).
 * It has been stated by Topala in an unknown twitch stream that the song MDK - Fingerbang presents a more inappropriate and vulgar name than any other level presented in the game. The level being made (if this were the song for 2.1) will be changed in order to be suited for the appropriate young teen audience.
 * This might be why Topala only released a hint at the soundtrack, and not the level name.
 * The black bat-like enemies displayed in teaser 4 closely resemble the "random enemy idea" shown by Topala just hours before the release of 2.0.
 * Topala stated before 2.0 that 2.1 would take about 1 or 2 months. However, it has been 7 months since Update 2.0 was released with very little teasers and sneak peeks.
 * In the sneak peek video, the fireballs rotating around the brick block closely resemble the Fire Bars from the Super Mario Bros. series.
 * The rock tileset in the 2nd teaser image resembles some of the tilesets of Scribblenauts.
 * One of the new jump rings is widely believed to be a mix between the pink and the blue rings (as in 2.0, the green was a mix of the yellow and blue jump rings.) The colour is also believed to be either purple or violet.
 * The color of the new spider-like form's portal is a dark indigo, unless another vehicle has been added, which is unlikely, since it has not yet been revealed, and Topala has never released 2 new vehicles in an update before.

Geometry Dash Lite Introductions

 * New Level "xStep"!
 * New achievements and rewards!
 * Bugfixes and tweaks.
 * Removed hacks and exploits.