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 or

Mobile APN Settings

Tethering APN Settings

External Antenna (Not Good)

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This antenna performed WORSE than the original supplied ones. Not an effective antenna.

Restricting Data Usage

Configuring your iPhone/iPad

Setup Low Data Mode

You should definitely turn on LOW DATA Mode on your new WIFI connection.

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• App Store: Video autoplay, automatic updates, and automatic downloads are turned off.
• Music: Automatic downloads and high quality streaming are turned off.
• Podcasts: The frequency of feed updates is limited, and episodes are downloaded only on Wi-Fi.
• News: Article prefetching is turned off.
• iCloud: Updates are paused, and automatic backups and iCloud Photos updates are turned off.
• FaceTime: Video bitrate is optimized for lower bandwidth.

Configure Your Mac

Mac OS doesn't have a low data mode but you can use an app called TripMode to track and limit data usage. 

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References