To merge PDFs offline on Android, install ProperPDF, open Merge PDF, select the files, drag them into order and save. The merge runs on the phone, so it works without a connection and nothing is uploaded. It's free on Android 8.0 and later; free exports carry a ProperPDF watermark, which Pro removes.

How to merge PDFs on Android

  1. Open ProperPDF and tap Merge PDF.
  2. Select two or more PDFs.
  3. Drag the files into the order you want.
  4. Save, then open the merged file to check it before sharing.
Merge PDF screen on Android
The Android Merge PDF screen used to combine your documents. View full-size screenshot

Good for private paperwork

Applications with their attachments, invoices, medical paperwork and scans of IDs are the kind of files you'd rather not send to a website just to staple them together.

After merging

Use Organize Pages to fix the order or remove a page. If the file is too large, Compress PDF (Pro) saves a smaller copy.

Questions

Can Android merge PDFs without an app?

Google's own apps (Files by Google and Google Drive) don't have a merge tool, so you need an app or a website. Some phone makers ship their own PDF tools. ProperPDF merges offline on any phone with Android 8.0 or later.

Is merging free on Android?

Yes. Without Pro the merged file carries a ProperPDF watermark.