Video: 4K @ 30-60 fps, plus 1080p or 2.7K at high frame rates (120 fps or more) for slow motion.
Photo: ~12-20 MP with good image quality.
Lens: Wide angle (≈ 140-170°), good aperture (lower f-number helps in low light).
Stabilization: At least electronic stabilization; optical or hybrid if possible.
Durability: Waterproof to 10-30 m (with housing or built-in); rugged/impact-resistant.
Battery: Enough for at least 60-90 minutes of continuous 4K recording; ideally swappable.
Size / Weight: Light, pocketable — around 50-100 g or less.
Display: Rear touch screen; possibly front indicator/display.
Connectivity: WiFi / Bluetooth; micro-SD support up to 128-256 GB.
Audio: Decent built-in mics; possibility of external mic input.