Also took it into local apple store and they said nothing wrong with it... All they did was a quick test
Your iPad may be doing things while it is sleeping. If you have push notifications on for numerous apps or perhaps a weak cellular signal that the iPad is trying to connect to while you have cellular on. These will use the battery. Losing 25% in a day would not be excessive if your iPad is working while sleeping.
So you bring up two issues, power and wi-fi network connectivity.
For starters, you should review these on power.
http://www.apple.com/batteries/ipad.html
http://support.apple.com/kb/HT4060
It would then be helpful to have some further info on your wi-fi environment. Home, work, public etc...
Have a iPad mini can fully charge it and can lose 25-30% charge without being used in a day, it won't connect to the Internet and when it does it lt 5-10 minutes poor connection.
