Annotate PDFs on Android
The UPDF for Android allows you to annotate your PDF in different ways like highlight, strikethrough, underline, squirrely line, pencil, shape, sticker, stamp, sticky note and more. Let's take a look at how you can annotate using each of these features:
Highlight Text
- Open the UPDF application on your phone.
- Now, open the PDF that you want to annotate. Click on the "Comment" icon at the bottom of the interface.

- Select the "Highlight" option and simply hover over the text to highlight it. You can also press the "Color" option next to the "Highlight" icon to choose a brush color and adjust the brush opacity.

Underline Text
- To underline text, tap on the "Comment" button.
- Now select the "Underline" symbol to enable it.

- Simply hover over the text that you want to underline. You can also press the "Color" option next to the "Underline" icon to choose the color and opacity of the underline.

Strikethrough Text
- To strikethrough text, tap on the "Comment" button.
- Now select the "Strikethrough" symbol to enable it.

- Simply hover over the text that you want to strikethrough. You can also press the "Color" option to choose the color and opacity of the strikethrough.

Add Squirrely Line
- To use a squirrely line on text, tap on the "Comment" button.
- Now select the squirrely line symbol to enable it.

- Simply hover over the text to apply a squirrely line on it. You can also press the "Color" option next to the "Squirrely Line" icon to choose the color and opacity of the squirrely line.

Add Text Comment
- To add a text comment, tap on the "Comment" button.
- Now select the "Text Comment" symbol (the T icon) to enable it. Click anywhere on the PDF where you want to place the text comment and start writing a comment in the text box.
- After writing a comment, click "Done" to proceed.

- You can click on any text comment that has been added to perform further actions, such as translating, using UPDF AI, editing content, changing properties, dragging it to change its position and so on.
- You can also press the "Color" option next to the "Text Comment" icon to choose the color of the text comment, change the font style and opacity.

Add Text Box
- To add a text Box, tap on the "Comment" button.
- Now select the "Text Box" symbol to enable it. Click anywhere on the PDF where you want to place the text comment and start writing a comment in the text box.
- After writing a comment, click "Done" to proceed.

- You can click on any text box that has been added to perform further actions, such as translating, using UPDF AI, editing content, changing properties, dragging it to change its position and so on.
- You can also press the "Color" option next to the "Text Box" icon to choose the font style, border thickness, opacity, text color, border color and background color of the text box.

Add Text Callout
- To add a text callout, tap on the "Comment" button.
- Now select the Text Callout symbol to enable it. Click anywhere on the PDF where you want to place the text callout and start writing a comment in the text box.
- After writing a comment, click "Done" to proceed.

- You can click on any text callout that has been added to perform further actions, such as translating, using UPDF AI, editing content, changing properties, dragging it to change its position and so on.
- You can also press the "Color" option next to the "Text Callout" icon to choose the font style, border thickness, opacity, text color, border color or background color of the text callout.

Add Sticky Note
- To add a sticky note, tap on the "Comment" button.
- Now select the "Sticky Note" symbol to enable it.

- You can press the Color option to choose the color and Style of the sticky note, then, click anywhere on the PDF where you want to place the sticky note and start writing a comment in the text box. Once done, click on a blank area of the page to finish adding the sticky note.
- You can click on any sticker that has been added to perform further actions, such as translating, using UPDF AI, editing content, changing properties, dragging it to change its position and so on.

Add Sticker
- To add a sticker, tap on the "Comment" button.
- Now select the "Sticker" symbol to enable it. Select a sticker and click anywhere on the PDF where you want to place the sticker.

- You can click on any sticker that has been added to perform further actions, such as copying, cutting, deleting, or dragging to change its position.

Draw on PDF
- To use a pencil or highlighter on your PDF document, tap on the "Draw" icon on the bottom bar of the UPDF. Then, select the "Pencil" symbol or "Highlighter" symbol as you like.

- You can press the "Color" option next to the "Pencil" symbol to select the pencil color and thickness from the range of available options. You can press the "Color" option next to the "Highlighter" symbol to choose the color, thickness, and transparency of the pencil.

- Now, simply draw on your PDF using the pencil.
- If you want to erase the pencil or highlighter marks, select the "Eraser" icon and click the transparent button next to it. Then, choose the eraser mode—either "Partial" or "Whole"—and select the eraser size. Now, you can swipe your finger across the screen to erase.

Add Shape
- To add shapes to a PDF document, click the "Draw" icon on the bottom bar of UPDF.
- Select the type of shape from the range of available options. You can add "Squares", "Circles", "Lines", or "Arrows" to your PDF. By clicking the "Color" icon next to these shape icons, you can also adjust the shape's border color, fill color, line thickness, and transparency.

- Swipe your finger on the screen to add a shape of your desired size. After adding a shape, you can click on it to perform further edits, such as editing, copying, deleting, or dragging its corners to adjust the shape's size and position.

Add Stamp
- To add the stamp to a PDF document, click the "Sign" icon on the bottom bar of UPDF.
- Now, tap the "Stamp" icon. UPDF has different types of stamps for you to select.

- Select one and click anywhere on the page to add a stamp.

You can click on any stamp that has been added to perform further actions, such as copying, cutting, deleting, or dragging to change its position.
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