Karabiner F1 to Launch Defined Applications?
The coding is similar to your question here: Karabiner F1 to Launch Safari?
You have to add a vkopenurldef tag though.

Some apps are already defined here:

/Applications/Karabiner.app/Contents/Resources/vkopenurldef.xml


After an update or an upgrade the file may be overwritten so customize your private.xml and add:

    &lt;vkopenurldef&gt;
        &lt;name&gt;KeyCode::VK_OPEN_URL_APP_Application&lt;/name&gt;
        &lt;url type="file"&gt;/Path/to/application&lt;/url&gt;
    &lt;/vkopenurldef&gt;
    &lt;item&gt;
        &lt;name&gt;F1 Application&lt;/name&gt;
        &lt;identifier&gt;f1_application&lt;/identifier&gt;
    &lt;autogen&gt;__KeyToKey__ KeyCode::F1, KeyCode::VK_OPEN_URL_APP_Application&lt;/autogen&gt;
    &lt;/item&gt;


Example:

    &lt;vkopenurldef&gt;
        &lt;name&gt;KeyCode::VK_OPEN_URL_APP_Notes&lt;/name&gt;
        &lt;url type="file"&gt;/Applications/Notes.app&lt;/url&gt;
    &lt;/vkopenurldef&gt;
    &lt;item&gt;
        &lt;name&gt;F1 Notes&lt;/name&gt;
        &lt;identifier&gt;f1_notes&lt;/identifier&gt;
    &lt;autogen&gt;__KeyToKey__ KeyCode::F1, KeyCode::VK_OPEN_URL_APP_Notes&lt;/autogen&gt;
    &lt;/item&gt;


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.