Matching control to data.
WHAT TO USE FOR SHORT TEXT
A single-line field, sized roughly to the expected content.
WHY SIZE MATTERS
Field width suggests expected length.
WHAT TO USE FOR A FEW OPTIONS
Radio buttons, all visible.
WHAT TO USE FOR MANY OPTIONS
A dropdown, with search where the list is long.
WHERE THE BOUNDARY SITS
Roughly five or six. Below that, show them.
WHY
A dropdown hides options and requires an extra action.
WHAT TO USE FOR MULTIPLE SELECTION
Checkboxes.
WHAT TO USE FOR ON AND OFF
A checkbox or a switch, with the effect clearly stated.
WHAT TO USE FOR DATES
A field accepting typed entry, with a picker as an option.
WHY BOTH
Pickers are slow for distant dates. Typing is faster for those who know the date.
WHAT TO SET ON MOBILE
The appropriate keyboard type: numeric for numbers, email for addresses.
WHY
It removes work and errors.
WHAT TO AVOID
Controls that hide what was selected.