You usually do not need a third‑party antivirus on a modern Android like the S26 Ultra if you install apps only from the Play Store and use basic caution, but extra security can be useful in riskier scenarios.����What Android and Samsung already provideAndroid includes Google Play Protect, which scans all apps on your device daily (including sideloaded ones), looks for harmful behavior, and can automatically block or remove known-malicious apps.��Google reports Play Protect now achieves very high malware detection scores in independent testing, and it continuously updates from Google’s cloud.��Samsung adds its own Knox security and secure enclave (Knox Vault / Personal Data Engine) on the S26 Ultra to encrypt sensitive data and harden the system and firmware.���When antivirus is not really necessaryIf all of these apply, a separate antivirus app is usually optional rather than essential:You only install apps from Google Play and reputable vendors.��You rarely use unknown public Wi‑Fi and avoid obviously sketchy links or attachments.�You do not sideload apps from random websites or stores.��In that situation, the built‑in protections plus common‑sense habits generally offer enough protection for most people.When antivirus can be a good ideaSecurity companies and some experts recommend an Android AV app in higher‑risk cases:���You often sideload apps (APK files) from outside the Play Store.You frequently use public or open Wi‑Fi, travel a lot, or connect to many unknown networks.You handle sensitive work data or do a lot of mobile banking and want extra web‑filtering/phishing protection.You like features such as anti‑theft tools, URL blocking for malicious sites, or stronger scanning than Play Protect alone.�����Independent tests have long shown that some third‑party security apps can detect more malware samples than Play Protect by itself, especially in older studies.��Practical recommendation for your S26 UltraIf you’re careful (Play Store only, cautious browsing, no shady APKs), you can safely rely on Google Play Protect plus Samsung Knox and skip separate antivirus for now.�����If you plan to sideload apps, use a lot of public Wi‑Fi, or just want a safety net, install a well‑rated, lightweight security app from a reputable vendor that scores highly in independent Android tests.����A good middle ground: periodically run an on‑demand scan with a trusted AV app (then disable always‑on scanning if you notice performance impact), while keeping Play Protect enabled and your phone fully updated.����