Final updates for ss-890c/rl-870c APP 20201202

Since the 890C has upgraded the background server and the latest version of the APP has been completed on the mobile phone, the customer will use it more quickly and stably. The old version of the APP will stop running today. Please inform the customer to upgrade the APP. Apple IOS users can Search for CUTTING download directly in the App Store of the system, Android users still download by scanning the code. All users who want to register must register in the new version of the APP