Bluetooth on the iPad is limited to headphones, speakers and keyboards. The ipad can also operate as a personal hotspot and connect to other devices for the purpose of sharing a data connection.
if you can't make a connection, there is a good chance that what you are trying to connect is incompatible.
EDIT: Ignore the above then. Try turning off Bluetooth, and restarting it. That might help. Make sure the speaker is in pairing mode when you turn on Bluetooth.
It is a speaker and it is compatible with iPad4, that is my iPad