Android handles PDFs better than people give it credit for. Between Google Drive's built-in viewer, the Files app's annotation tools, and a handful of capable browser-based editors, you can do most everyday PDF work on a phone or tablet — no app store search required.
What's built in across modern Android
Android fragmentation is real, but the basics are now consistent across most devices:
- Google Drive's PDF viewer opens any PDF and supports basic annotation: highlight, underline, sticky notes.
- Files by Google can preview and share PDFs. On most Pixel and Samsung devices it can also create a PDF from selected images.
- Samsung Notes / S Pen integration on Galaxy devices supports rich annotation, handwritten notes overlaid on a PDF, and OCR of handwriting.
- Print-to-PDF: any document, web page, or photo can be saved as a PDF via the system Print dialog → "Save as PDF."
For most users, those features cover the daily 90% — sign a form, mark up a draft, save a webpage as a PDF for offline reading.
When the built-in tools aren't enough
Real edits — changing existing text, swapping a logo, rebuilding a form — need a proper editor. Options:
- Browser-based editor. Docento.app runs in Chrome on Android with no install — drop a PDF, edit, save. Works locally so the file doesn't leave your phone.
- WPS Office PDF editor. Capable, free tier with ads.
- Adobe Acrobat Reader. Free for viewing, paid subscription for editing.
- Xodo. Strong all-rounder for annotation and form-filling, lighter on text editing.
The browser route has the big advantage that the same workflow works identically on desktop, iPad, and other phones. No re-learning per device.
Filling forms on Android
The interactive form case (real fillable fields baked into the PDF) works well in most readers — tap, type, save. The harder case is the "scanned form with empty boxes," which most readers can't actually fill. Workflow:
- Open the PDF in an annotation-capable reader.
- Use the text tool to type into each box.
- Sign at the bottom with the signature tool (or a saved signature image).
- Save and share.
For more, see our form-filling guide.
Scanning documents
Android phones make excellent document scanners. Three good options:
- Google Drive's scan button (the camera-plus icon). Auto-detects edges, deskews, lets you scan multiple pages, exports as PDF.
- Adobe Scan. Stronger OCR than Drive's scan, free.
- Microsoft Lens. Good edge detection, integrates with OneDrive and OneNote.
The result is a multi-page PDF with a real text layer — searchable, copy-pasteable, ready for forms or contracts. For more on the OCR side, see our OCR explainer.
Signing PDFs
Android supports the same three signature flavours as iOS:
- Drawn signatures — finger or stylus.
- Image signatures — photograph a signature on paper, drop it as an image.
- Digital signatures with certificates — supported by Adobe Reader and a few specialised apps; needed for legally significant documents in some industries.
Legal weight differs by jurisdiction. See digital vs electronic signatures for the specifics.
Combining, splitting, and rearranging
The native tools don't really do these. Browser tools handle them well — drag thumbnails to reorder, select page ranges to split, add pages from another PDF to merge. Docento.app supports all three in the browser.
For more on splitting, see how to split a PDF. For combining, see how to combine PDF files.
Compressing for upload
Android PDFs from scans can easily exceed the 5-25 MB limit most upload portals impose. Two options:
- Re-scan at lower quality — most scan apps have a quality toggle, and "medium" is fine for forms.
- Compress with a browser tool that runs locally — no upload, no privacy risk.
See reducing PDF file size for general approaches.
Storage, sync, and privacy
A few Android-specific points:
- Photo gallery sync. PDFs created from camera scans may also leave the original photos in your gallery. Delete the photos if the document is sensitive.
- Cloud backup. Many Android backup tools sync
Downloads/automatically. Check what's syncing before editing confidential documents. - App permissions. PDF apps that ask for "all files access" without good reason should be avoided. Browser-based tools sidestep this entirely.
Tablet vs phone
Tablets with stylus support (Galaxy Tab, Lenovo Tab, etc.) are good replacements for a laptop for most PDF work. Margin notes feel natural; long contracts are easy to read; signatures are crisp. Phones are fine for filling and signing, painful for restructuring or heavy text editing.
Conclusion
Use the built-in tools for sign-and-share, browser tools for real editing, and a scan app for capturing paper. Docento.app handles editing in the browser without uploads. For the cross-device picture, our iPhone editing guide and Chromebook editing guide cover the rest of the modern lineup.