What Is Cobalt Tools?
Cobalt Tools (or Cobalt.tools) is a media download service that enables users to download video, audio, and image content from a wide variety of social and media platforms by simply pasting a share link.
It is open-source software with a codebase available on GitHub under the AGPL-3.0 license. 
The tool describes itself as “a tool that makes downloading public content easier … paste the link, get the file, move on.” 
While many people refer to a “Cobalt Tools APK,” there is no confirmed official Android app version widely recognized; instead, the service is typically accessed via web instances or custom deployments.
Supported Platforms & Media Types
Cobalt Tools supports downloads from a broad set of platforms. According to its site, these include: 
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YouTube (videos, shorts, music)
TikTok (videos, audio)
Instagram (posts, reels)
Facebook (videos)
Twitter / X (videos, voice)
Pinterest (media)
Snapchat (stories, spotlights)
SoundCloud (music, audio)
Vimeo (videos)
Reddit (videos, GIFs)
Dailymotion, Bilibili, Twitch, Tumblr, VK, Streamable, Byte, Coub, LinkedIn, and more 
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It acts as a kind of “universal downloader” for content from these platforms.
Key Features
Here are some of its principal features and characteristics:
Feature    Description
Ease of use    Copy the media-sharing link, paste it into Cobalt Tools, and download. 
High-quality download    
Offers downloads in good output quality formats. 
Ad-free experience    
Claims to be free from advertisements or popups during its core service. 
Cross-platform support    Works via web; accessible from Android, iOS, Windows (via browser) 
Keyboard shortcuts    
For faster workflow/efficiency (on desktop) 
Open source & transparent    
The source code is public, and the developers disclaim liability for content usage. 
No caching of content    
The service claims it doesn’t store or retain downloaded media; it functions more like a proxy.