The app does what it says - i.e., initiate a call from an icon on the home screen - but it takes approximately 10 seconds for the call to actually be initiated, which is hardly "speed dial".
The problem is that the app does not directly start the call but it opens up a website with some code (I am not a developer so dont understand the details), which eventually starts the call. All this opening up of Safari, loading the page with the code, then opening up the phone app and starting the call apparently takes time… too much time.
I dont know if there is a better way of doing this in iOS but recommend you dont get this app. You got a call started faster the regular way.