This article explains how to pin a message on top of a Telegram group using an Android mobile or tablet.
Steps
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Step 1. Open Telegram
The icon looks like a white airplane on a blue background. It is usually found on the home screen or in the app drawer.
This feature is only available for supergroups. If you haven't created one yet, do so before proceeding
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Step 2. Tap the group the message you want to pin was sent to
If you haven't been in this group for a while, you may need to scroll down to find it.
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Step 3. Tap the message you want to pin
A pop-up window will appear.
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Step 4. Tap Fixed
A confirmation message will appear.
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Step 5. Decide whether to notify other members
If you want them to be notified once you have fixed the message, check the box next to "Notify all members". If not, remove the check mark.
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Step 6. Tap OK
The message will be pinned at the top of the group.