There was quite a lot of commotion and hype recently about 1 year signed IPAs and about the possibility to even avoid the expiration of the certificate using Immortal, but how Immortal works? We're talking about a tweak, so the limitations are obvious, yet still, this might be the best tweak for you if you happen to have deployed a lot of apps in IPA format.
Now, deploying IPAs can be done via Cydia Impactor, but the free developer account (anyone who's not paying 100$/yr to Apple) will have a 7 days signed limitation for every IPA and not more than 3 devices per Apple ID. With Immortal, these things are in the past, as this simple yet reliable tweak kicks the hell out of the signature system on the device. Of course, you should not forget that, being a tweak, it requires you to be Jailbroken in order for Immortal to work. This is where misunderstandings appear, so I will explain it as well as I can.