You can cancel you Familonet premium subscription anytime, there is no period of notice. However you have to cancel before the renewal date, otherwise your subscription will be extended.
To cancel your subscription on iOS:
- Go to Settings > iTunes & App Store.
- Tap your Apple ID at the top of the screen.
- Tap View Apple ID. You might need to sign in or use Touch ID.
- Tap Subscriptions.
- Tap the subscription that you want to manage.
- Use the options to manage your subscription.
To cancel your subscription on Android:
- Go to play.google.com/store/account.
- Find the subscription you want to cancel.
- Click Cancel Subscription.