Will jailbreaking my iPhone 4s ios 7 delete my apps?

I have a lot of apps and games that I'm pretty far into and I wouldn't want to start all over if my apps were to get deleted. So I was wondering if I will still be able to use itunes and redownload all my apps if they were to get deleted and if they'd still have all my info saved.
Next, will jailbreaking my iPhone cause it to crash like I hear some people say it will, while others say they have no issues.

There's no jailbreak released for ios7 yet, but when there's it won't delete any apps. Jailbreaking won't make your phone crash as long as you don't install too many apps/tweaks from cydia or any unsafe ones.