Builds expire after 7 days though. If you forget to build it again you'll be stuck with a non-working app that crashes back to home screen as soon as you open it.
You could resign the app using Cydia Impactor. This avoids the rebuilding process, and keeps the app data on the device.
Interesting, I'm not familiar with it. Still have to do this every week though? And I assume it only works over a USB connection, not over wifi?
Yes, and yes.
Hm, I honestly don't plug my iOS devices into my computer much anymore, but I bet that process could be automated to run when the computer detects the device which would make it less painful. Thanks for the heads up!
Oddly enough, not always. I have a just-for-me app working on my phone that I last built on December 3rd.