Applications installed like this have limited functionality--such as no push notifications--and some types of application are simply not supported (such as VPN

Applications installed like this have limited functionality--such as no push notifications--and some types of application are simply not supported (such as VPN clients: Apple seems to have structured everything in order to best support the China Communist Party's control regime here). You can only have three such self-signed applications installed at once, and you have to keep reinstalling them every 7 days (which is more annoying than you would expect if you haven't really had to do it constantly).