If you use the CASIO WATCHES app, you might have noticed that some of its features are currently unavailable. This is because Casio has temporarily suspended certain app services following the discovery of a critical security issue affecting PHP, a programming language widely used to power web services.

The Japanese watchmaker announced the suspension on 22 October 2026, although its official notice states that it took effect a day earlier, on 21 October. The company says the move is a precautionary measure to protect customer information, as parts of the app’s service rely on PHP.

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