Panda Helper is a great alternative to Cydia, which requires jailbreaking and the use of an unofficial app store. It lets you download apps from anywhere, and unlike Cydia, it's not validated by Apple. However, you should be aware that downloading apps from unreliable sources may compromise the operating system of your phone and may even prevent you from securing your Apple ID. In addition to Panda Helper, you can download applications from Panda Helper to your device.
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