Doesnt work

I paid for and downloaded the app and it doesnt work. I touch the button, the screen goes black for two seconds and then right back to my home screen. Sent an email to the company and got a response asking about my phone and iOS, like I didnt check that already, havent heard from them since.
Dont waste your time and money with this app.

Crusty Salt about Marine Bells - Ships Bells To Go, v1.5