Seriously suggest you don't use that app. Last time I tried to run it (wanted the lock screen message) it took me an hour to get the phone usable again (and still had a few apps that got broken by it that I haven't quite figured out how to fix without a full wipe yet).
And by "usable" I don't mean "Oh no it lagged my phone" I mean "Oh no I can't get it go get past halfway through the Sprint animation without locking up".