Galaxy Z Flip 5G

Requires: One UI 2.0 or later, including One UI Core (One UI 1.5 on Galaxy Note10); not on Android Go models

Single press always wakes or locks the screen. Natively, Long press only offers a digital assistant (Gemini by default from One UI 7), Bixby or the power-off menu, so it cannot open our app. Labels changed over time: One UI 6 and earlier say Side key and Open app (pick the app with the gear icon); One UI 7 and later say Side button and Apps. When the phone is locked, Open app asks for an unlock before the app opens (SamMobile, One UI 1.5; Samsung does not document this for later versions), so test whether our entry can show over the lock screen. Emergency SOS also listens to the side key: 5 quick presses on One UI 5.0 and later (Send SOS messages used 3 or 4 presses on older versions), so repeated double presses must be spaced out. On Galaxy Z Flip, Samsung says to keep the phone open when using side-key shortcuts. Samsung notes the options vary by model, region, carrier and software version.

Requires: Good Lock with the RegiStar module (Samsung, free), One UI 5.0 or later

Samsung's store listing and support page say RegiStar can run features by long-pressing the side key; that one of those features is opening any app comes from tech press and community guides, and the RegiStar menu labels above come from those guides too. The hold replaces the long-press action, so the power-off menu is then reached with Side + Volume down or the Quick panel. Good Lock is region-limited: SamMobile reported it reaching Mexico, Colombia, Brazil, Argentina, Chile and Peru in December 2022, and Samsung began a global rollout plus a Google Play listing (One UI 7 or later) in April 2025; check the Galaxy Store in the user's country. Listed only for Galaxy S, Z and Note models; not confirmed on A, M or XCover models. It feeds the same side_key input as the double press, so if both are mapped, either gesture counts as one side-key event.

Requires: Good Lock with the RegiStar module, One UI 5.0 or later; Galaxy S and Z Flip models only

Samsung limits back tap to Galaxy S and Z Flip phones (Z Fold4 gets a force-press action on the screen instead, not covered here). Launch coverage says it does not work on the lock screen, with the screen off or sleeping, or at 15% battery or less, so it only helps while the phone is unlocked and in use. Users report unreliable detection; RegiStar has a sensitivity setting. Good Lock availability is region-limited (see the RegiStar side-key entry).