
Add a border to a slide in Keynote on iPhone
To add a border — such as a solid or dotted line — around a slide, you first add a square shape to the slide, then change the shape’s attributes so it behaves like a border. For example, you change the size of the shape, give it no fill (as opposed to a colour fill) so that it doesn’t obscure other objects on the slide and so on.
If you want several slides to use the same border, create a slide layout that includes the border.
- Go to the Keynote app  on your iPhone. on your iPhone.
- Open a presentation. 
- Tap  in the toolbar, then tap in the toolbar, then tap . .
- In the Basic category, tap a square or rounded rectangle to add it. 
- Drag the blue dots that appear around the shape until the outer edges of the shape form the border size you want. 
- Tap  , then tap Style. , then tap Style.
- Tap Fill, tap Preset, then swipe left and tap No Fill.  - If you want the bordered area to have a background colour, tap a fill option. You can make the object more transparent so it doesn’t hide other objects on the slide. 
- Tap  to go back to the Style tab. to go back to the Style tab.
- Tap to turn on Border. 
- To select a border style, colour and width, use the controls that appear.  
- To change the transparency, drag the Opacity slider (at the bottom of the controls). - If the shape is filled with a colour, its transparency also changes. 
- To move the border behind all the objects on the slide, tap Arrange, then drag the slider all the way to the left. 
- To lock the border so it doesn’t get moved accidentally, tap Arrange (at the top of the controls), then tap Lock.  
- When you’re finished, tap anywhere on the slide to dismiss the controls.