CAn you merge two PDFs in the iOS app?
A short answer is "no". Sorry.
If you subscribe to the Adobe PDF Pack online service, you can use the "Combine Files" feature to combine files and images into a single PDF file via the web interface (https://cloud.acrobat.com/combinepdf) on a desktop computer.
Combine files to PDF
But the "Combine Files" feature is not available in the Acrobat DC mobile for iOS or Android. Sorry for the inconvenience.
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