When you use LPD Cust, you have open options to configure any thing, may it be HTML page, URL, webdynpro app, portal page, transactions, webDJava, any other.
When you select SAP UI5 app, you can give URL of your ui5app(bsp app) and launch it directly, without actions. But for Fiori apps, you need to go with lpd_cust configuration.
regards,
Tejas