The iLOQ S50 app for iOS works on models running iOS 15 or a later version. However, considering the variety of form factors and designs in different iPhone models affecting NFC performance, it is not guaranteed that the app works seamlessly in all iPhone models. Therefore, it is recommended to test the application on your phone before taking it into full use. 

Before installing the app, make sure that:

1. Your phone is NFC compatible and supports NFC tag read/write functions.
   1. Please note that iPads do not have NFC support.
2. You know where the NFC antenna is in your phone.
   1. This application uses the wireless energy harvesting capability of NFC technology for lock opening. To ensure smooth and efficient energy flow between the phone and the lock during opening, the NFC antenna on the phone must be placed accurately against the lock’s antenna knob. The NFC antenna may be in different places depending on the phone model. With current iPhone models, the NFC antenna is somewhere at the top. To check the location of the NFC antenna, refer to your phone’s operating instructions or contact the manufacturer. Please keep in mind that NFC performance may be affected if your phone has a cover.
3. Your phone is not jailbroken.
   1. Jailbreaking exposes devices to security threats. The iLOQ S50 app cannot be installed and used in jailbroken devices.
4. Your phone operating system is running the latest available version.
   1. This is to ensure your phone is protected by the latest security patches. For security reasons, it is important to always keep the operating system updated to the latest version.

The iLOQ S50 app is free to install from the Apple App Store. Note: you must have an Apple ID account on your device to install apps from the App Store. After installation, the app must be registered as a key to a locking system before it can be used.