Synchronicity

The currently installed Apps for your iPad and iPhone cannot be directly synchronised. However, for any new Apps purchased and installed from the App Store, you can configure your devices to automatically install compatible Apps on other devices.

On both your iPad and iPhone:

Settings > App Store > [Automatic Downloads]

• App Downloads - set to ON
• App Updates - set to ON
• In-App Content - set to ON

you can restore one of them from the backup of the other, if they run the same ios version

though while they will start out the same then they will not automatically sync as in remove apps when deleted from the other, and it's up to apps if the data will be synced