Need to update ipad 4 16gb from OS 8

[cleverwabbit]

Just found out my mail won't work on OS 8 anymore. I haven't wanted to updates because of memory but now it seems like I am forced to. Is there any way I can update to OS 9 instead? Will OS 10 max out my memory? I already have to delete so much not to run out now.
Thanks

 

[Jupiter7]

You can't update to IOS 9 as Apple has ceased signing it. If there is not enough room on your iPad for iOS 10, you will not be able to install it without deleting some of your data. That said, you may well be able to re-download any deleted Apps after the installation is complete.