Karabiner F1 to Launch Safari?
Solution 1:
Modify private.xml and add:
<item>
<name>F1 Safari</name>
<identifier>f1_safari</identifier>
<autogen>__KeyToKey__ KeyCode::F1, KeyCode::VK_OPEN_URL_APP_Safari</autogen>
</item>
Then enable it in Change Key. Depending on your settings (Consumer Keys or F1-F12 for the F-keys) in System Preferences -> Keyboard -> Keyboard -> F-key behavior you may have to hit the fn-key also.