Stay mobile Add Underline to PDF on OPPO For Free

Drop document here to upload
Select from device
Up to 100 MB for PDF and up to 25 MB for DOC, DOCX, RTF, PPT, PPTX, JPEG, PNG, JFIF, XLS, XLSX or TXT
Note: Integration described on this webpage may temporarily not be available.
0
Forms filled
0
Forms signed
0
Forms sent

Discover the simplicity of processing PDFs online

Card illustration
Upload your document in seconds
Card illustration
Fill out, edit, or eSign your PDF hassle-free
Card illustration
Download, export, or share your edited file instantly
Top-rated PDF software recognized for its ease of use, powerful features, and impeccable support
Users Most Likely To Recommend - Summer 2025
Grid Leader in Small-Business - Summer 2025
High Performer - Summer 2025
Regional Leader - Summer 2025
Easiest To Do Business With - Summer 2025
Best Meets Requirements- Summer 2025

Every PDF tool you need to get documents
done paper-free

Card illustration

Create & edit PDFs

Generate new PDFs from scratch or transform existing documents into reusable templates. Type anywhere on a PDF, rewrite original PDF content, insert images or graphics, redact sensitive details, and highlight important information using an intuitive online editor.
Card illustration

Fill out & sign PDF forms

Say goodbye to error-prone manual hassles. Complete any PDF document electronically – even while on the go. Pre-fill multiple PDFs simultaneously or extract responses from completed forms with ease.
Card illustration

Organize & convert PDFs

Add, remove, or rearrange pages inside your PDFs in seconds. Create new documents by merging or splitting PDFs. Instantly convert edited files to various formats when you download or export them.
Card illustration

Collect data and approvals

Transform static documents into interactive fillable forms by dragging and dropping various types of fillable fields on your PDFs. Publish these forms on websites or share them via a direct link to capture data, collect signatures, and request payments.
Card illustration

Export documents with ease

Share, email, print, fax, or download edited documents in just a few clicks. Quickly export and import documents from popular cloud storage services like Google Drive, Box, and Dropbox.
Card illustration

Store documents safely

Store an unlimited number of documents and templates securely in the cloud and access them from any location or device. Add an extra level of protection to documents by locking them with a password, placing them in encrypted folders, or requesting user authentication.

Customer trust by the numbers

64M+
users worldwide
4.6/5
average user rating
4M
PDFs edited per month
9 min
average to create and edit a PDF
Join 64+ million people using paperless workflows to drive productivity and cut costs

Why choose our PDF solution?

Cloud-native PDF editor

Access powerful PDF tools, as well as your documents and templates, from anywhere. No installation needed.

Top-rated for ease of use

Create, edit, and fill out PDF documents faster with an intuitive UI that only takes minutes to master.

Industry-leading customer service

Enjoy peace of mind with an award-winning customer support team always within reach.

What our customers say about pdfFiller

See for yourself by reading reviews on the most popular resources:
I love PDF filler. I was delighted that I was able to import a form from my email to PDF Filler as the form was not listed as available on your program. Very easy to use. t
Elvira W
2017-04-07
I am a rookie user born of necessity since some pdf forms I needed to fill out on a website were not cooperating. I'm hooked. Very convenient and easy to use and saved me on more than one occasion (same type of issue). Now that my "crisis" is over, I want to delve into the product and actually unlock it's potential.
Lenny J
2018-02-19
Directions for completing fillable forms were very clear, easy to follow, and concise. This is a great product for someone who is in need of fillable forms on a regular basis. Highly recommended.
Anonymous Customer
2019-05-05
What do you like best?
The ability to edit practically any document, within reason. As a Finance professional, it's much easier to add a JPEG of a signature to hundred of checks rather than signing them by hand. My carpal-tunnel free wrists thank you!
What do you dislike?
I don't have any negative comments; everything that the program promises, it delivers.
Recommendations to others considering the product:
It's a great value for a relatively low monthly cost.
What problems are you solving with the product? What benefits have you realized?
It allows for rapid addition of signatures to checks, contracts, affidavits, etc.
User in Outsourcing/Offshoring
2019-08-15
Locating forms is a little… Locating forms is a little slow/complicated. Also would like to be able to save information that will be repeated on other fillable forms.
Mary Wyatt
2020-02-14
Hi only needed PDF filler for one doc Hi only needed PDF filler for one doc. Trusted the site enough to add my credit card, used the program and then deleted the account. Seems like this business is legit and would use again.
peter deutschmann
2022-07-18
What do you like best? Redacting of documents and contracts, signing contracts What do you dislike? I haven't found anything to dislike. There is nothing missing for my use. Recommendations to others considering the product: Quick and easy What problems are you solving with the product? What benefits have you realized? Redacting of documents is quick and easy. Benefit is that it eliminates the need to print, sign and scan.
Lisa Martucci
2022-02-08
It was easy to use and I was able to print without watermarks. It also saves my work virtually and I can resume anytime. The additional features it had was really useful to share files and even notarize.
Jerome M
2020-11-19
So far so good. I like the friendly interface and the different options of sending processed files. I would like to request developers to incoporate "rotating page" for some documents that may be uploaded upside down
Samson Clarence E
2020-08-19

Is it possible to Add Underline to PDF on OPPO?

Are you fed up of having to carry your laptop around anywhere you go, so that you can keep working with that document? Perhaps you have lost clients just because of an inability to Add Underline to PDF on your OPPO? By using pdfFiller, you're getting the solution that frees you from relying on not cloud-based software, to enable you to work from any device, anywhere.

pdfFiller is a web-based PDF editing program with advanced functionality for smartphone users and enables you to Add Underline to PDF on OPPO just the same way it does on your desktop. You can actually do both and get the documents instantly synced to the cloud. Use the website, desktop app, or the mobile app. Check out the list below for the best features available on smartphones:

01
Simplify collaboration. Highlight content or add comments for your colleagues
02
Convert files. Save your records as files in PDF, Word, Excel, or PowerPoint formats
03
eSign documents. Create a legally-binding signature and send a form for signing in seconds
04
Cover sensitive data. Use the Blackout option to hide delicate information that shouldn’t be spread to third parties
05
Request additional authentication. Ask recipients to confirm their identity by taking a photo or linking social media profiles
06
Add new objects. Insert texts, crosses, checkmarks, images, text boxes, or simply draw on a document
07
Export content. Share samples via links, emails, messengers, or fax

If you jump into pdfFiller's functionality, you'll be able to explore even more helpful tools and make on-the-go document management flow significantly more productive and straightforward. Consider using it to avoid wasting your energy on carrying your laptop all the way around. Get everything you need for professionally dealing with PDFs. Register now!

Stay Mobile: Add Underline to PDF on OPPO

Easily add underlines to your PDFs on your OPPO device. This feature is designed to enhance your reading and editing experience, making it simple to emphasize important information.

Key Features

Intuitive user interface for effortless navigation
Single tap access to underline tool
Compatible with various PDF formats
Save and share edited documents instantly

Use Cases and Benefits

Highlight key points in reading materials for study or review
Mark important terms in contracts and business documents
Enhance productivity by organizing information visually

This feature solves your problem of keeping track of vital information within your PDF documents. With just a few taps, you can underline text that matters most to you, ensuring that nothing is overlooked. Stay organized and focused with the ability to highlight significant entries directly on your OPPO device.

Get documents done
from anywhere

Create, edit, and share PDFs even on the go. The pdfFiller app equips you with every tool you need to manage documents on your mobile device. Try it now on iOS or Android!

For pdfFiller’s FAQs

Below is a list of the most common customer questions. If you can’t find an answer to your question, please don’t hesitate to reach out to us.
What if I have more questions?
Contact Support
Open a PDF file and select the Annotate tab. Select the Highlight , Underline , or Strikeout tool. Choose the color for each tool on the sidebar on the right. In the underline tool, you can also switch between a squiggle and a straight line there.
To accent text or images, tap and hold the Highlight icon. Select either the Highlight, Underline, or Strikethrough option, then at the bottom of the screen, expand the Styles menu to further customize your selection.
To create a highlight, tap the center of your screen to bring up the Action Bar. Tap the Annotation Toolbar, then the Highlighter icon. Drag the marker with your finger to the end of a sentence or paragraph to highlight the text.
Adding lines to a PDF document Choose Tools > Text Tool. Choose Notes > Line. Drag in the document until the line is located where you want, and drag the end points until it points where you want.
Choose Tools > Comment, and select the Highlight Text tool , the Strikethrough Text tool , or the Underline Text tool .

Video instructions on how to Add Underline to PDF on OPPO

#1 usability according to G2

Try the PDF solution that respects your time.
Users Most Likely To Recommend - Summer 2025
Grid Leader in Small-Business - Summer 2025
High Performer - Summer 2025
Regional Leader - Summer 2025
Easiest To Do Business With - Summer 2025
Best Meets Requirements- Summer 2025