Freezes device

I am loathe to negatively review apps however this one is warranted. The UI on Calvetica is beautiful however the app freezes both my iPhone 4 as well as my iPad 2 (for approximately 5 seconds) whenever I leave the app. Everything locks up and this only happens with Calvetica. Support form the developers has been non-existent

Airborneaussie about Calvetica Calendar, v4.4.1