Fit your data to the column width using the Wrap Text option.
- Select a cell, a range of cells or the whole worksheet.
- Open the Cell settings panel by
- tapping the
icon at the top toolbar, or
- tapping the Cell option in the pop-up menu.
- Tap the
icon to the right of the 
Text Format section.
- Swipe up to see the
Wrap Text switcher and turn it on.
If you change the column width, data wrapping adjusts automatically.
You can also select a cell/cell range and tap the Wrap option from the pop-up menu that appears. When data wrapping is enabled, the Unwrap option becomes available in the pop-up menu.