You can change your monthly plan into a yearly one at any point you want. Here are the steps you'll need to follow:
1. Go to “Settings” which are on the main menu of your iPhone.
2. Click on “iTunes & App Store” which is located towards the bottom.
3. Click on “Apple ID” in the list that opens up.
4. Sign into your Apple ID.
5. Click on "My Subscriptions" in the page that opens up.
6. Choose "Yearly Subscription".
7. For more information you can contact Apple through this link:
1. Go to Google Play Store.
2. Click on the Menu tab on the upper left corner.
3. Click on “My Account” in the menu that opens up.
4. Click on "My Subscriptions" in "My Account".
5. Choose "Yearly Subscription".
6. For more information you can contact Google Play through this link: