This article explains how to reduce the mobile data consumed by Snapchat by turning off automatic download.
Steps
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Step 1. Open the Snapchat application
The icon depicts a white ghost on a yellow background.
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Step 2. Swipe down on the main screen
A menu will appear, where you can see your profile and the various options available to add and view your friends.
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Step 3. Click on ⚙️
This button is located in the upper right corner of the screen. Snapchat's main settings menu will appear from the right.
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Step 4. Scroll down and select Manage
This option is found in the section of the menu titled "Additional Services".
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Step 5. Swipe the Travel Mode switch to activate it
It will turn green. Snapchat will stop downloading snaps and stories automatically. You will need to click on a snap or story to download its content.