Due to popular demand, the flattening capability has been restored in Acrobat Reader 18.12.00 for iOS (released on December 14, 2018).
Step 1: Enable the "Share a Flattened Copy" option
Once the "Share a Flattened Copy" option is enabled, a copy of the PDF document containing comments (e.g. highlight, underline, strikethrough, notes, freehand drawing), form fields, and signatures will be flattened when shared so that they are no longer editable in the copy.
- Tap the Profile icon in the top bar.
- In the Settings screen, tap Preferences.
- Enable the "Share a Flattened Copy" option.
Please note that the comments and form fields in the original PDF document will remain editable.
Step 2: Share a flattened copy
Your share sheet options may vary depending on the apps installed on your iPhone/iPad.
- Open the PDF document that you would like to share.
- Tap the Share icon in the top bar.
- Tap "Share a Copy" at the bottom of the screen.
Note that you do not have to sign in to share a copy.
- Select an option from the iOS share sheet.
Examples: AirDrop, Mail, Gmail, Copy to <cloud_storage>, Save to Files
Please note that Acrobat does not support the flattened copy option for encrypted or password-protected PDF documents.