If an app provides an interface via the Perch control panel, it must register itself with Perch. This is done in the perch/addons/apps/my_app/admin.php file.

    $this->register_app('my_app', 'My App', 5, 'An exciting app of goodness', '1.0');

The register_app() method takes 6 arguments prior to this Perch version it took 5:

Type Description
String Your app ID
String A name/label for your app
Int The priority in which is should appear on the Perch tab bar
String A brief description (unused currently)
String A semantic versioning version number
Bool Whether the app should display in the app menu

There’s no good way to determine the priority setting you should give. If your app does something administrative, it would make sense to give it a high number to shift it to the end of the line of tabs (Pages is always the first item). Really this is more to give the user control of the apps they have installed.

Once an app is registered, it appears on the tab bar.

Asserting a required version

If your app relies on a certain version of Perch to run (perhaps using features that an older install of Perch would not have available), you can assert that your app requires a minimum version:

$this->require_version('my_app', '1.7.3');

If the version of Perch is not greater than or equal to the number you state, Perch will throw an error preventing the user from continuing until they update or uninstall the app.


The admin.php file is also the place to add your app’s autoloader so that your class files can be found. You’ll do the same in your runtime.php file for any classes needed by page functions.

    if (strpos($class_name, 'MyApp_')===0) {
        return true;
    return false;

Template handers

If your app uses a template handler for handling custom template tags, you can also register that in your admin.php file.