Q: Can I switch the data on an iphone 4 and 4s?

Hey cpdion,

I understand that you wish to make a backup of your phone and put your information on a newer device that you are planning on purchasing. This can be done through the instructions in the articles below:

How to back up your devices using iCloud or iTunes - Apple Support

https://support.apple.com/en-us/HT203977

Restore your device from an iCloud or iTunes backup - Apple Support

https://support.apple.com/en-us/HT204184

Keep in mind that a backup of a newer iOS version cannot be applied to a device running an older iOS version:

Learn more

iOS does not support restoring a backup from a newer version of iOS to a device using an older version of iOS.

Example: Restoring a backup from an iOS 7 device to an iOS 6.x or earlier device is not supported.

If you wish to transfer content from a device with a newer version of iOS to a device using an earlier version, follow these steps to transfer the content to your computer, and then use iTunes to sync the content to your device.

 

Note: Some content, including messages, app data, and other settings, cannot be transferred using this method.

iOS: Unable to restore from backup of a newer device - Apple Support

https://support.apple.com/en-us/HT203434

Thanks for being a part of the Apple Support Communities!

Cheers,

Braden