Keyboard Maestro Control
Keyboard Maestro Control is the iPhone adjunct to Keyboard Maestro. It allows you to log in to Keyboard Maestro and execute macros from your iPhone, iPod touch (or iPad in compatibility mode).
You need to ensure that the Keyboard Maestro Web Server is running and configured with a username and password.
After that, get Keyboard Maestro Control from the App Store (it's free).
Launch it, and then in the settings, add a new connection. If your Mac has a static IP address and/or static domain name, you can use that, otherwise (as is far more common) you will only be able to access it on your local Mac network (unless you configure port forwarding on your ADSL modem - which is far beyond the scope of this wiki I'm afraid!). If you are on your local network, click the > icon to the right of the host name, and select your Mac running Keyboard Maestro.
Enter the username and password you set up in Keyboard Maestro’s preferences.
Once connected and authenticated, you can execute any macro you have configured in Keyboard Maestro.
There are plans to eventually add iPad support and support for custom icon palettes which would work well with the iPhone.