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For maximum privacy, you can create secret chats that use end-to-end encryption. These aren't stored on Telegram's servers, so you can only access them with your specific phone. If one party deletes a message, it disappears on both devices. And you can specify a self-destruct period for all media if you like. Once you and your contact have both shared your live locations with each other, Telegram will show both parties on either map, which allows them to track each other. Once here, choose the proximity alert button on the top right. You can choose your distance parameters here while the app shows you a live preview of the circular distance you have chosen. Any user can upload large files and media, each up to 2 GB in size and enjoy unlimited storage in the Telegram Cloud for free. With Telegram Premium, subscribers will now be able to send 4 GB files – enough space for 4 hours of 1080p video, or 18 days of high-quality audio.

Premium users get increased limits for almost everything in the app. With Premium, you can follow up to 1000 channels, create up to 20 chat folders with up to 200 chats each, add a fourth account to any Telegram app, pin 10 chats in the main list and save up to 10 favorite stickers. Voice messages can be converted to text for those times you don't want to listen, but want to see what it says. You can rate transcriptions to help improve them. Next time you want to quickly move a piece of media from one device to another, Telegram has you covered. The Saved Messages chat is your own personal cloud scratchpad for keeping a record of information that you can access on any device where you're logged into Telegram. Lock Your Chats

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Custom Folders To lock a chat go to Settings->Privacy and Security->Passcode Lock and enable it. Once you create a passcode and enable it, you will be able to lock and unlock your chats by tapping on the lock icon at the top right of the app.