First of all, we must know that the download channels of Apple's regular applications all know the App Store. Apple's signature originally appeared to facilitate the internal testing of large enterprises. As long as Apple's signature is made, the application can be directly installed on Apple's mobile phone without going through the App Store, but when the signature expires, the software can naturally no longer be used.

Either renew the fee or re-sign it. In fact, Apple's corporate signature is very simple. For micro-diversion distance, just upload ipa file to the platform, select the package and submit the signature.