Airside vs must-clear: budget pure transit first
Jewel’s vortex and most mall floors are landside (reachable after clearance or before departure immigration). Pure transit: if the next flight stays airside in the same terminal and time is tight, stay airside — do not exit just for Jewel then re-clear. Market talk often cites ~4–5 hours connection before a real Jewel browse (walks, security, boarding buffer) — shorter = corridor pass-through, not an itinerary. HK arrivals still need the free official SG Arrival Card; see the arrival guide.
Landing hour vs pure transit: do not jam the CBD
Overnight / short stop after landing: clearance + bags + SimplyGo, then one hour at the vortex is enough; Canopy Park bridge is separate. Pure transit with 4–5h+: one Jewel loop + a meal — keep the day’s axis on the airport east line; do not also jam Marina Bay, Chinatown or Sentosa. Pulau Ubin is a full east slow day (last bumboat ~evening) — another day.
Who should deepen / who only passes through
Deepen if connection buffer is comfortable, or arrival / departure day locks the airport east line as the only axis. Pass through if under ~four hours, or the short trip already locks Bay / Sentosa — Jewel is a photo stop, not a city-time thief.