Zoho-backed homegrown messaging platform Arattai is preparing for a major update, with end-to-end encryption set to go live on Tuesday night, founder Sridhar Vembu announced in a social media post.

Vembu said the platform has several more "cool features" lined up, which will follow once "this big transition" is complete.

"Please update the Arattai app from the Play Store/App Store and please encourage your contacts to do so. The end-to-end encryption will be enabled Tuesday night IST," Vembu wrote on X.

He clarified that end-to-end encrypted messaging will only work when both users in a conversation have updated to the latest version of the app.

"If you are on the latest Arattai version and your contact is on the latest version, you will only be able to use end-to-end encrypted chat with that contact," he said.

When both parties are updated, the app will automatically generate a new end-to-end encrypted chat session, while the older, non-encrypted chat will be archived.

"So you cannot continue the old chat session with any contact who is in the end-to-end encrypted version of the app. The old chat screen will simply redirect you to the end-to-end chat screen," Vembu explained.

For contacts still using an older version of Arattai, users can continue using the old chat for only three more days. After this transition period, the app will upgrade all users to the latest version, making end-to-end encryption mandatory across the platform.

Group chats are not yet protected with end-to-end encryption, though Vembu said the feature will be introduced in the coming weeks for groups up to a certain size.

"End to end encrypted chats will get a backup option in about two weeks," he added.

Arattai recently surged in popularity following a wave of support from ministers, startup founders and CEOs, leading to rapid daily sign-ups and widespread sharing of invites—ironically, including through numerous WhatsApp groups.