The system occupies swipe-up from the bottom
Aliases: home indicator · swipe up home · gesture bar
What it is
Bezel-less systems took swipe-up from the bottom edge as a shell command: a short swipe goes Home, a held or farther swipe enters multitasking. That trace belongs to the system, not the current app. An app may draw its own buttons on the bottom edge. It cannot assume a swipe that starts on the indicator will be delivered to its callbacks.
Why it happens
The home indicator is a visible anchor for a system gesture whose recognizer captures contacts entering from the bottom before the app. Short displacement plus lift maps to Home; longer displacement or a pause maps to the switcher. Bins vary by OS, but every bin ends at the system layer. A fullscreen app can ask to thin the indicator; it can rarely actually turn the channel off—that would remove the system-wide escape. So any motion “from the very bottom upward” hits the system first. A game thumbstick drawn on the bottom edge may send the first upward push to the desktop.
Studying it
Under default gesture navigation, swipe up from the bottom edge, from 1 cm above it, and from mid-screen. Log Home, multitasking, or an in-app panel. Split fullscreen games, ordinary apps, and apps with their own tab bar. Turning on virtual nav keys is the control: bottom swipe-up should become available to the app. Compare indicator height and capture band across OS versions.
Where it stops holding
A device with a physical Home key or always-on three-button nav does not give bottom swipe-up to the system. A landscape tablet sometimes parks the gesture bar on the long edge; it is still a “from the outer short side” variant. Cars and TVs may have another task bar at the bottom, with different occupancy. Android skins disagree on swipe-up bins; do not freeze one system’s table.
Applying it
- Treat the system bottom edge as off-limits: do not hang a core action on a swipe that starts at the very bottom.
- In fullscreen, keep the system indicator visible, or at least do not draw a critical control into the capture strip.
- Swipe up from the real indicator. You should go Home or into multitasking, not open your panel. If your panel opens, you occupied the system trace.