This application tries to wake up a sleeping computer in the local network.
According to the WOL (Wake on LAN) definition, you need to create a so-called "Magic Packet" and send this packet to the MAC address of the network card on the computer to be awakened.
WakeApp is a small app that does exactly this. Here you can add several computers, which you need to remotely wake. For each computer you need at least the MAC address of the network card. This address can be easily found using the ipconfing command (Windows). It is also often displayed in the router.
For WOL to work, the computer has to be prepared. The correct settings must be made in the BIOS as well as in the system. Several information can be found on the Internet.