iA Writer is file storage provider agnostic but we recommend iCloud for the best experience across most devices.
If you are already using Writer for iOS or Writer for Mac apps and have enabled iCloud, you’ll find a dedicated iA Writer folder in your iCloud Drive. To access this on a Windows device you can download and install iCloud for Windows.
Note that prior versions of iCloud for Windows suffer from a number of compatibility issues. Updating to the most recent version of iCloud for Windows before adding iCloud folders to Writer is highly recommended.
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iCloud 
iA Writer is file storage provider agnostic but we recommend iCloud for the best experience on Mac: Set Up iCloud iCloud is on by default, but you can check with the following steps: Confirm iCloud is active macOS 1. Add your Apple ID to System Settings → Apple ID → iCloud 2. Check System Settings
iA Writer is file storage provider agnostic but we recommend iCloud for the best experience on iPhone: Set up iCloud iCloud is on by default, but you can check with the following steps: Confirm iCloud is active iOS 1. Add your Apple ID to Settings → iCloud 2. Check Settings → iCloud → iCloud Drive
iA Writer is file storage provider agnostic but we recommend iCloud for the best experience on iPad: Set up iCloud iCloud is on by default, but you can check with the following steps: Confirm iCloud is active iPadOS 1. Add your Apple ID to Settings → iCloud 2. Check Settings → iCloud → iCloud Drive
iA Writer is file storage provider agnostic but we recommend iCloud for the best experience across most devices. If you are already using Writer for iOS or Writer for Mac apps and have enabled iCloud, you’ll find a dedicated iA Writer folder in your iCloud Drive. To access this on a Windows device you can