Decimal meter by Dominic Dawson

I down loaded this app from the App Store on my Ipad a Ndebele used it for 2 days my husband is takings peach therapy for Parkinsons disease I loved the way it was working. However when it asked me to update my I pad I can not get the program back when I originally down loaded it worked fine and I loved it I need to know how to get it back I have been trying for 2 days help

Mashpotatp about Decibel Meter Plus Pro