Here is my app, to illustrate what I mean by "crash" and so you can see what I'm trying to do. I used the Tab function to build four tabs. One shows a history chart with the three greenhouse temperatures, and an average temp in a separate indicator in the image center. There are also LEDs to show when the fan, louver, misters, pump, and two irrigation systems are running.
On the next tab, I've placed all the commands. There are sliders for various ON/OFF temperature-related functions, and three buttons to manually start the misters and two irrigation systems.
The third tab contains a pair of timers to run the irrigation systems. And the Tweet widget.
The fourth tab (not shown) has a red button in the middle labeled "reset". I tried to write a software reset function but that doesn't appear to work either.
You can see the "crash" in the first tab, on the history graph. The app stops showing data or accepting commands at random intervals. The reset button I wrote doesn't work, either. It is not clear if the sketch continues to run without the Blynk app or not - I've been at work and have only had this up and running for the past few days.