Survey results released by cybersecurity company Kaspersky on September 4 across the Asia-Pacific (APAC) region show that 71% of users in Vietnam consider smartphones their primary device for accessing the Internet.

Notably, Vietnamese users store sensitive data on mobile devices at significantly higher rates than the regional average. As many as 57% keep images of identification documents such as citizen ID cards, passports or insurance documents directly on their phones, compared with an APAC average of 49%.

Alongside personal photos and videos, stored by 65% of respondents, Vietnamese users also rely on smartphones to manage their finances and work. Some 40% store passwords and login credentials, compared with a regional average of 34%, while 36% keep bank account information and 52% store work emails and messages. In addition, 20% have begun saving their interaction histories with artificial intelligence (AI) tools.

Despite mobile devices becoming central repositories for virtually every aspect of users’ digital lives, security habits have not kept pace with the growing volume of sensitive information stored on them. According to the company’s data, its systems blocked nearly 8.5 million web-based cybersecurity threats targeting users in Vietnam in 2025 alone, the highest figure in Southeast Asia.

Ngo Tan Vu Khanh, Kaspersky’s country manager for Vietnam, said smartphones are no longer simply communication devices but have become “digital vaults” containing everything from financial information and contracts to identity data.

“Users need to move from simply storing data to actively protecting it. For example, documents should be kept in encrypted folders rather than left in the photo gallery, dedicated digital identity applications such as VNeID should be prioritized instead of photographing physical documents, and a virtual private network (VPN) should be enabled when using public Wi-Fi,” he recommended.

Cybersecurity expert Anton Kivva shared a similar view, saying users often install security software on their personal computers while overlooking their smartphones, turning mobile devices into the weakest link against cyberattacks.

Three principles for protecting mobile data

To reduce the risk of data leaks when a device is lost or compromised by malware, experts recommend three principles:

Do not store everything on a single device: Avoid making a smartphone the only place where important data is kept. Users should regularly back up information to cloud services or use separate encrypted storage, such as a Secret Vault, specifically for scans of documents and passwords.

Set up multi-layered protection: Install mobile security tools capable of checking applications before installation and automatically detecting and blocking malicious or fraudulent links in real time.

Enable risk-response measures: Turn on device location and remote data-erasure features, such as Find My Device on Android and iOS, in case the phone is lost or misplaced. Users should also enable automatic backups, configure the screen to lock automatically when the device is no longer in use, and avoid leaving phones where they can easily be stolen or unattended in public places.

Du Lam