What can I do when a customer fails to use an Android installation package received from me to install an app and the system displays a message indicating that there is no app to open the installation file?

If you transfer an Android installation package (.apk file) through WeChat, the ".1" suffix will be added to the file name extension by default. The mobile phone's operating system will then fail to identify the file. To resolve this issue, tell the customer to first check whether the file name extension is .apk. If not, remove the added suffix in an application such as the file manager. Alternatively, send an app download link or QR code to the customer.