in support page http://support.apple.com/kb/ht3325 are steps to connect ios devices as follows
- On your iOS devices, choose Settings > Wi-Fi to verify both iOS devices are on the same wireless network.
- On the iPad running Keynote, open your Keynote presentation.
- Tap the Tools icon in the toolbar.
- In the Tools menu, tap Settings.
- In the Settings menu, tap Remote.
- In the Remote Settings menu, turn on Enable Remotes.
- On the iPhone, open the Keynote Remote app.
the striken out step is not accurate, you can find the remote option in Presentation Tools
