WhatsApp Spy is an app that allows you to find out when all of your WhatsApp contacts last connected without letting them see that you are online.
So, you just have to install this app on your mobile phone and choose what connection you want to use (whether you only want to use a WiFi connection, a data connection, or both).
Once you have set up this specific configuration, you will see a list of all of your WhatsApp contacts and you just have to click on a person to see what time they last connected or if they are online or not.
You can see the connection status of your contact in a matter of seconds. Meanwhile, your status won't change at all, so you can open WhatsApp without updating the time that you last connected and without letting anyone know that you've done so.
