下面是一个示例代码，可以用来检查应用是否已发布并在9/10台设备上显示，但不是全部设备。

import StoreKit

func checkAppAvailability() {
    let productIdentifiers = Set(["your_product_identifier"])
    let request = SKProductsRequest(productIdentifiers: productIdentifiers)
    
    request.delegate = self
    request.start()
}

extension YourViewController: SKProductsRequestDelegate {
    func productsRequest(_ request: SKProductsRequest, didReceive response: SKProductsResponse) {
        if let product = response.products.first {
            let totalDevices = response.products.count
            let availableDevices = totalDevices - 1 // Assuming 1 device doesn't have the app
            
            if availableDevices >= totalDevices * 0.9 {
                print("App is available on 9/10 devices.")
            } else {
                print("App is not available on 9/10 devices.")
            }
        } else {
            print("Unable to retrieve product information.")
        }
    }
    
    func request(_ request: SKRequest, didFailWithError error: Error) {
        print("Failed to retrieve product information: \(error.localizedDescription)")
    }
}

你需要将your_product_identifier替换为你应用的内购产品标识符。此代码使用SKProductsRequest来检查应用内购产品的可用性。在didReceive回调中，我们可以根据产品数量来判断应用是否可用于9/10的设备。