If your application gets bigger, it makes sense to structure Controllers with sub-folders. But it takes a little more effort than just moving the files here and there. Let me explain the structure.
For example, we want to have a sub-folder app/Http/Controllers/Admin and then inside of it we have our AdminController.php, that's fine. What we need to do inside of the file itself:
1. Correct namespace - specify the inner folder:
namespace App\Http\Controllers\Admin;
2. Use Controller - from your inner-namespace Laravel won't "understand" extends Controller, so you need to add this:
use App\Http\Controllers\Controller;
3. Routes - specify full path
This wouldn't work anymore:
Route::get('admin', 'AdminController@getHome');
This is the correct way:
Route::get('admin', 'Admin\AdminController@getHome');
And that's it - now you can use your controller from sub-folder.
