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Well-Known Users of SQLite

SQLite is used by literally millions of applications with literally billions and billions of deployments. SQLite is the most widely deployed database engine in the world today.

A few of the better-known users of SQLite are shown below in alphabetical order. This is not a complete list. SQLite is in the public domain and so most developers use it in their projects without ever telling us.

Adobe uses SQLite as the application file format for their Photoshop Lightroom product. SQLite is also a standard part of the Adobe Integrated Runtime (AIR). It is reported that Acrobat Reader also uses SQLite.
Airbus confirms that SQLite is being used in the flight software for the A350 XWB family of aircraft.
Apple uses SQLite in many (most?) of the native applications running on Mac OS-X desktops and servers and on iOS devices such as iPhones and iPods. SQLite is also used in iTunes, even on non-Apple hardware.
Bentley Systems uses SQLite as the application file format for their Microstation CAD/CAM product.
Bosch uses SQLite in the multimedia systems install on GM, Nissan, and Suzuki automobiles. (link)
The increasingly popular Dropbox file archiving and synchronization service is reported to use SQLite as the primary data store on the client side.
Expensify uses SQLite as a server-side database engine for their enterprise-scale expense reporting software.
Facebook uses SQLite as the SQL database engine in their osquery product.
SQLite is the primary meta-data storage format for the Firefox Web Browser and the Thunderbird Email Reader from Mozilla.
Flame is a malware spy program that is reported to make heavy use of SQLite.
We believe that General Electric uses SQLite in some product or another because they twice wrote to the SQLite developers requesting the US Export Control Number for SQLite. So presumably GE is using SQLite in something that they are exporting. But nobody (outside of GE) seems to know what that might be.
Google uses SQLite in their in the Android cell-phone operating system, and in the Chrome Web Browser.
Intuit apparently uses SQLite in QuickBooks and in TurboTax to judge from some error reports from users seen here and here.
McAfee uses SQLite in its antivirus programs. Mentioned here and implied here.
Microsoft uses SQLite as a core component of Windows 10, and in individual numerous products.
The Navigation Data Stanard uses SQLite as its application file format.
The popular PHP programming language comes with both SQLite2 and SQLite3 built in.
SQLite comes bundled with the Python programming language since Python 2.5.
The REALbasic programming environment comes bundled with an enhanced version of SQLite that supports AES encryption.
The RedHat Package Manager (RPM) uses SQLite to track its state.
There are multiple sightings of SQLite in the Skype client for Mac OS X and Windows.
The Tcl/Tk programming language now comes with SQLite built-in. SQLite works particularly well with Tcl since SQLite was originally a Tcl extension that subsequently "escaped" into the wild.
A representative of Toshiba wrote to the SQLite developers and requested the US Export Control Number for SQLite. We infer from this that Toshiba is exporting something from the US that uses SQLite, but we do not know what that something is.