Why merge PDFs
Merging is useful for applications, reports and receipts where one file is easier to send.
OmniDoc is still under development; this guide describes general methods that work with common Android PDF tools.
Basic steps
Open a PDF tool with a merge function, select files in order, reorder if needed, and save the combined file with a clear name.
Reordering and removing pages
After merging, use a page view to drag pages into order and delete blanks or duplicates.
Watch file size
Merged scans can be large. Compress if a portal has a size limit.
Preparing your files
Before merging, gather all the files in one folder and give them clear names, for example 01-cover.pdf, 02-application.pdf and 03-certificates.pdf. Numbering helps you select them in the right order. Check each file opens correctly, and remove blank pages or duplicates first if possible. If some documents are photos, convert them to PDF before merging so everything shares the same format.
Typical uses
Merging is common for job applications that ask for one combined file, visa or university submissions, expense claims with several receipts, and project reports assembled from different sources. In each case, a single well-ordered PDF is easier for the recipient to read and less likely to get lost than many separate attachments.
Page size and orientation
Files from different sources may have different page sizes, such as A4 and Letter, or a mix of portrait and landscape pages. Most merge tools keep each page's original size. If you need a uniform look, rotate pages that appear sideways and consider whether the recipient will print the file. Consistent orientation makes the document easier to read on screen.
Naming and storing the merged file
Give the merged file a descriptive name that includes your name and the purpose, like ali-babar-application-2026.pdf. Store it in a folder you can find later, and keep the originals in case you need to rebuild the file with changes.
Checking the result
Scroll through the merged file to confirm order, look for missing pages, and check the final size against any upload limit. If it is too big, compress it before sending.
Adding bookmarks and a cover page
For long merged files, a cover page listing the contents helps the reader. Some PDF tools also let you add bookmarks, which appear as a clickable outline in most viewers. Even a simple first page saying 'Contents: application form, CV, certificates' makes a submission look organised and easier to review.
Merging on a slow or low-memory phone
Large scans can strain older phones. Merge in batches, close other apps, and make sure there is enough free storage for the new file, which will be roughly the size of all inputs combined. If the app crashes, compress large inputs first and try again.
Merging sensitive documents
Identity documents, bank statements and medical records deserve extra care. Merge them on your device rather than through unknown websites, avoid leaving copies in shared folders, and delete temporary files after sending. If a recipient accepts password-protected PDFs, consider adding a password and sharing it separately.
Privacy
Prefer tools that process files on your device for sensitive documents, rather than uploading to unknown servers.
Frequently asked questions
Is there a limit to how many PDFs I can merge?
It depends on the app and your phone’s memory.
Will merging reduce quality?
No, merging alone does not change page quality.
Can I merge images too?
Many tools convert images to PDF pages first.
Can I reorder pages after merging?
Yes, most tools have a page view for reordering.
Will links survive merging?
Often, but check them in the merged file.