How to Merge PDF Files:
1. Launch PDF NOW app on your iPhone or ipad.
2. Go to the toolbar on top of this app.
3. Click on "Merge" files.
4. Add files from your device. Or you can download files from your Google Drive and Dropbox before step 2.
5. Choose the PDFs you want to merge and click "Merge" button in the bottom of screen.
6. In this step, it allows you to reorder the files.
7. Click the "Start" button and it'll automatically merge your PDFs into one PDF.