If you use social networking apps, internet browsing, music, then it is more than good. out of box close to 9-10 gb available space. About the battery, you need to calibrate the battery first to get the maximum of it. I use 3g and wifi all the time, play vids, lot of youtube etcc and it lasts for more than a day .
you need to disable some apps that you do not use.turning off apps may help preserve battery life.go to SETTINGS>GENERAL>BACKGROUND APP REFRESH> then choose what apps you want to disable. I hope this will help you:)
