What are you trying to do with this connection? It's likely the iPad doesn't support the Bluetooth profile needed.
See here for what is supported: http://support.apple.com/kb/HT3647
To move Contacts, calendar data, etc. information from Android to iOS you can use third party Apps on both devices the Apps will move this information to the "Cloud" with one App and back to your other device with another App.
See, for example, PhoneCopy at http://www.phonecopy.com/en/