my wife deletes emails from her android phone and they also delete from my ipad .How can I prevent this.
It sounds like both her phone and your iPad are set up with Microsoft Exchange Server.
Exchange has some great benefits as your email account syncs instantly with our email server. When either of you send an email, you can both then see the sent email in both devices' sent items. Changes made to the contact list will also show up on both devices. And the great benefit that can also be a great nuisance is that when one of you deletes an email, it gets deleted from the other's device too.
An option is to turn off Exchange on both of your phones and move to POP/SMTP settings where both devices will download the emails but the emails will stay on the email server. But your contact lists wouldn't sync with the email server and you could only use the contact lists that are stored on the devices.
To turn off Exchange and move to POP/SMTP, the settings can be found at How to set up email - iPhone/iPad (iOS 6) and How to setup email on an Android device.
Hey tpesl, have you had time to check if one or both of your phones are on Exchange server? Exchange is definitely more convenient but when there's two people accessing the same email account on two different devices, it can get a bit confusing. POP/SMTP might be a better option for you but it means that you can't sync your contacts and sent items.
Retrieving data ...