Viettel’s Tammi, a communications and digital-utility platform, has passed 20 million users, Viettel Telecom announced on 27 October 2026, less than three months after its public launch in August 2026. The app has held a top spot among free downloads on both the App Store and Google Play in Vietnam. Tammi was listed on the app stores in April 2026 but was initially for internal use only, before its public debut in August. From 5 million users recorded in August, Tammi has grown fourfold.
One in ten users is on another network
The most striking detail is not the 20 million figure but who the users are. About 10% of Tammi users subscribe to other carriers, such as VinaPhone and MobiFone, meaning one in ten Tammi users is not a Viettel subscriber. The app is reaching beyond Viettel’s own subscriber ecosystem, attracting people who have never used the carrier’s services.
That matters because Tammi is no longer just a companion app for Viettel subscribers. When users of other networks install it and keep using it, Tammi has a chance to stand as an independent communications platform, competing on experience rather than on a ready-made subscriber base.
Used every day, built on security
In October 2026, Tammi’s daily-to-monthly active user ratio (DAU/MAU) reached nearly 30%, meaning nearly three in ten monthly users open the app every day. The figure reflects genuine engagement rather than downloads or registrations. Viettel has not disclosed an absolute daily-user number, so no daily figure can be derived from this ratio. For a platform launched less than three months ago, a ratio near 30% suggests Tammi is already becoming part of many users’ daily routines.
On security, Tammi verifies accounts by phone number and OTP, supports linking with VNeID for stronger identity verification, requires re-verification when users change phones, and applies end-to-end encryption to supported communications. Tammi OA verifies organisational accounts, helping users recognise official channels from businesses, agencies and organisations. On utility, users get free online meetings with up to 100 participants for 120 minutes per session, 5GB of free Viettel Cloud storage, the Tammi Book reading feature, an AI assistant inside chat, and free mobile data when using Tammi for Viettel subscribers.
From telecom carrier to tech company
Built on Viettel’s technology, telecom infrastructure and experience serving tens of millions of customers, Tammi is one step in Viettel’s strategy to transform from a telecom carrier into a technology company. The goal is not just a messaging app but a safe, easy-to-use space that understands and cares for users’ needs. Tammi is gradually building a digital-services ecosystem for everyday needs, connecting people with each other and with businesses, agencies and organisations through Tammi OA.
The 20-million-user milestone is an important starting point. For Viettel, Tammi’s long-term success will rest not only on how many people sign up, but on becoming a familiar, useful and trusted platform in the daily lives of Vietnamese users.
Sources: Viettel Telecom, press release, 27 October 2026; VnExpress.
