1. Using the Microsoft PowerPoint App

Steps:

Download the App: Install the Microsoft PowerPoint app from the App Store.

Open the App: Launch the app and sign in with your Microsoft account if required.

Locate the File: Tap on “Open” and navigate to the location of your .PPTX file (e.g., OneDrive, iCloud, or the Files app).

Open the File: Select the .PPTX file to open it in the PowerPoint app.

2. Using the Files App

Steps:

Locate the File: Open the Files app on your iPhone or iPad.

Navigate to the File: Find the .PPTX file stored locally or in a cloud storage service linked to the Files app (e.g., iCloud Drive, Google Drive, Dropbox).

Tap to Open: Tap on the .PPTX file. If you have a compatible app installed (like PowerPoint or Keynote), it will give you the option to open the file with that app.

3. Using the Keynote App

Steps:

Download Keynote: Install the Keynote app from the App Store if it’s not already installed.

Open Keynote: Launch the app.

Import the File: Tap on the “+” icon to create a new presentation, then select “Import” to locate and open the .PPTX file from your files or cloud storage.

Edit and View: The file will be converted to Keynote format for viewing and editing.

4. Using Google Slides

Steps:

Download Google Slides: Install the Google Slides app from the App Store.

Open Google Slides: Launch the app and sign in with your Google account.

Import the File: Tap on the “+” icon and select “Import” to find the .PPTX file stored in Google Drive or another connected cloud storage service.

Open the File: Select the .PPTX file to open it in Google Slides.

5. Using a Third-Party App

Steps:

Download a Compatible App: Install a third-party app like WPS Office or Polaris Office from the App Store.

Open the App: Launch the app and navigate to the location of your .PPTX file.

Open the File: Select the .PPTX file to view or edit it within the third-party app.

Email Attachments: If you receive a .PPTX file as an email attachment, you can usually tap on the file within the Mail app, and it will offer you the option to open it in a compatible app.

Cloud Storage Integration: Ensure your cloud storage services (like iCloud, Google Drive, or Dropbox) are integrated with the Files app for easier access to your .PPTX files.