protect the app itself if you wanted to.I use this app:https://play.google.com/store/apps/details?id=com.thinkyeah.smartlockfree&hl=enI hate having my whole phone locked down just to protect a few privacy sensitive apps...so that app was a huge win for me....as far as delay timer.... I dunno the use scenario for that...But Hangouts will handle SMS now in case you didn't know. So it can be your only app for all messaging needs. .