The Numeric Input widget allows to decrement/increment values by touching “-” and “+”. Touching the numeric value launches the keypad to enter a new value.
This all works fine until you hide and un-hide the widget (needed to unclutter the GUI for certain modes).
Blynk.setProperty(V3, "isHidden", true); // Hide Pressure SP Widget
// ...
Blynk.setProperty(V3, "isHidden", false); // Show Pressure SP Widget
Now touching the numeric value does not launch the keypad anymore but “+” and “-” still work.
Closing and re-opening the App fixes the problem.