Touch targets should be at least 44×44pt.
Anything tappable hits 44pt — pad small icons rather than shrinking the hit area.
A 24px trash icon crammed next to an edit icon looks tidy on a designer's monitor and becomes a coin-flip on a phone, where a fingertip covers roughly 44px of glass. Users tap edit when they meant delete, or miss entirely and jab twice. Pad the hit area to at least 44 by 44 points, keep the icon its small visual size, and the taps land first time. Apple's Human Interface Guidelines have used 44pt as the floor for years for exactly this reason.
The 44pt floor is written for touch. A mouse or trackpad is far more precise, so a dense desktop toolbar can use smaller controls without the same miss rate. Even then, keep destructive actions comfortably sized and separated, and remember many “desktop” users are on touchscreens or have reduced motor control, so erring larger rarely hurts.
A music player's Skip control is a 28pt icon squeezed into the transport bar. Driving or walking, users jab at it two or three times before it catches.