Citing the change log for AltStore v1.4.9, it seems that this version incorporates an important fix for a crashing issue on devices running iOS or iPadOS 13 or older.
While those running iOS or iPadOS 14 or 15 can quickly and easily update to the latest version of AltStore by using the integrated “Update” button in the app, the AltStore team strongly recommends that those on iOS or iPadOS 13 or older update AltStore by re-sideloading the latest version with AltSever.
Once installed, the newest version of AltStore should provide a better user experience with fewer unexpected app crashes, and that’s one reason why iDownloadBlog recommends all current users go ahead and update to the latest version of AltStore at will.
Please note that there isn’t currently an update for the computer-based AltServer program, as today’s update only applies to the handset-based AltStore app.
While AltStore is popular among jailbreakers who need to sideload the Odyssey, Taurine, and unc0ver jailbreak apps, it’s also widely used by those wanting to sideload their own .ipa files to bypass the often neutering restrictions imposed by the App Store. This often entails modified apps, unsigned apps, and even game emulators.