- Published
- October 18, 2026
- Category
- Product
- Related surface
- PaperBuild
Open PaperBuild, add your page images, check their order and tap Build PDF to create one document on your Android phone. You can crop pages and choose a page style before exporting. The free workflow supports up to 10 pages per document and does not need Pro.
The screenshots show PaperBuild 1.1.0 on a Samsung Galaxy A55 using fictional weekend-plan pages. The separate QA build uses the released app interface. Document names, sizes and dates in the pictures are examples. Tap a screenshot to view it at full size.
Add the page images
Tap Add images to choose one or more images with Android’s system picker. PaperBuild does not request broad access to your gallery. A cloud-backed picker may need to download a selected image before the app can use it.
Alternatively, tap Scan to open your phone’s camera app. Photograph the page and confirm the capture there. PaperBuild uses the resulting image; it does not directly control the camera or automatically detect the page edges.
For a first try, photograph a non-sensitive sample page in good light. Keep the page flat and check that the text is readable and not cut off.
Crop and arrange the pages
Each page card has controls to move the page up or down, rotate it, remove it from the draft or open Crop. Check the order before exporting.
In Crop, drag the corners to select the part you want to keep. Adjust crop bounds provides percentage controls if you prefer precise entry. Use Restore full page to reset the selection, then Apply crop to keep it or Cancel to leave without applying a new crop.
PaperBuild saves the current draft privately on the device. You can resume it after closing the app. New document clears that draft and its private page copies, not your original images or completed PDFs.
Choose PDF settings
Under Make it yours, enter a document name and expand the settings button below it. Choose A4 or US Letter. For page style, use Colour, Grayscale or Contrast. These change the exported page appearance; they do not recognise or turn text into editable text.
Keep Standard file size for the free workflow. Smaller · Pro is an optional paid setting. Review readability when choosing a page treatment or smaller export.
Build and keep a PDF copy
Tap Build PDF and wait for Ready to share. Read the summary and check the number of pages. Tap Open PDF to inspect the result in a PDF viewer before sending it.
Use Save PDF to save a copy to Downloads/PaperBuild. On Android 8 and 9, saving may require storage permission. Android 10 and newer use scoped storage without that permission.
Share PDF opens Android’s sharing options. Check the chosen app, destination and audience. The receiving app may upload the copy when you send it; local PDF creation does not make every later sharing destination private.
Find and manage Recent PDFs
Completed documents are also stored in PaperBuild’s private Recent PDFs library. Open Recent PDFs · Free from the main screen. Use Open PDF to view a document or More options to share, save to Downloads, rename it or move it to Removed PDFs.
Moving a library document to Removed PDFs is reversible. Open Removed PDFs and use Restore PDF if needed. Permanent deletion requires confirmation and cannot be undone. Removing the private copy does not delete copies saved or shared elsewhere.
What optional Pro adds
PaperBuild Pro is a one-time Google Play purchase, not a subscription. It adds smaller exports, pages beyond the free 10-page limit, PDF merge and page-range extraction, password-protected output, custom text watermarks, page numbers and saved export presets. Your local price is shown before purchase; use the same Google Play account to restore ownership.
PDF tools do not accept password-protected input documents. Use an unlocked working copy. Editing invalidates digital signatures; extraction discards bookmarks and page labels. Watermarks and page numbers are visible additions, not redaction or digital signatures.
Output passwords are not saved in drafts or presets, and forgotten passwords cannot be recovered. A PDF’s output password does not encrypt the original images or draft working files. The private library does not generate previews for password-protected PDFs.
What stays on the phone
PaperBuild processes documents on-device, has no internet permission and does not upload your pages. There is no PaperBuild account, advertising or analytics. Google Play uses its own connectivity for optional purchases and ownership checks. Your camera app, image provider and chosen sharing destination have their own behaviour and privacy terms.
Read the PaperBuild privacy policy for storage, permissions and purchase details.
Before sharing, check page order, cropping, orientation and readability. This is an image-to-PDF workflow, not OCR, automatic document edge detection or a PDF text editor.