ShareViewController.swift

func saveImageToAppGroupFolder(imageData: Data) {
	guard let containerUrl = FileManager.default.containerURL(forSecurityApplicationGroupIdentifier: "your-group-identifier") else { return }
	let filename = "shared.jpg" // 
	let fileURL = containerUrl.appendingPathComponent(filename)
	do {
		try imageData.write(to: fileURL, options: .atomic)
	} catch {
		return
	}
}