This is quite a while ago, like 2011 ish, but I used to do sms and call spoofing with my jailbroken phone. That being said, a jailbroken iphone is extremely vulnerable.

Find the repo for app sync unified and install that along with Filza file manager and NewTerm terminal for starters. A fun one is iflooder, have to find the deb on github but I can get a link if you need it as I just installed it myself

By itself jailbreaking doesn’t give you any benefit to hacking. It does however give you the basis on which to start. Unsigned code is basically a requirement for running anything (developer side-loading is a thing but not all code can be run from a apps sandbox). Direct hardware access is another thing, putting a devices WiFi chip into monitor mode is a good example. Personally I have a old iPhone6 running CheckRa1n that serves as a adhoc automated SMS device using SSH. However, regardless of opinion or personal preference (I have used a iPhone extensively in the past and continue to use a iPad for general use) android based phones will always be the better option for this type of stuff simply due to its usage of the Linux kernel, more open nature and less device specific hardware. Unless your willing to code stuff yourself there just really isn’t much avaliable

Could you point me in the right direction on which jailbreak software you used? I have a iPhone XS I would like to jailbreak and play around on.