Blame Apple for that. They require you to disable security by jailbreaking your phone in order to install Cydia. On Android you can easily install other appstor

Blame Apple for that. They require you to disable security by jailbreaking your phone in order to install Cydia. On Android you can easily install other appstores while keeping security intact. If you don't want other app stores, just deploy an MDM profile that bans them.