> For the complete documentation index, see [llms.txt](https://docs.blynk.io/en/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.blynk.io/en/blynk.apps/widgets-app.md).
# Widgets (app)
Widgets are pre-designed pieces of Graphic User Interface. Each widget performs a specific input/output function when communicating with your hardware or end-user.
Widgets can be found in the **Widget Box.** While in dev mode scroll the list and tap on the Widget you need to add it to the Grid. Tap the Widget to set it up.
There are 6 major types of widgets:
* **Header widgets** – UI elements that can be added to the header of your device dashboard.
* **Controllers** – UI elements used to send data to hardware. For example: buttons, switches, sliders, joysticks, etc.
* **Displays** – UI elements used to visualize the incoming data. LEDs, Charts, Gauges. etc.
* **Interface** – Elements to build user-friendly UI. Tabs, Drop-down menus, various inputs, etc.
* **HTML Widget** – a widget you build yourself with HTML, CSS, and JavaScript, connected to device data (datastreams, metadata, etc.).
* **Other** – special widgets that don't belong to any category.
Widgets availability is based on the plans and corresponding limits.
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