You can easily cancel your subscription.
Go to App in the Air > Profile > Settings > Manage Subscriptions > you will be redirected to the iTunes app. Select App in the Air and tap Cancel.
Another way for iOS: Device Settings > click on your account > iTunes & App Store > click on your Apple ID at the top > View Apple ID subscriptions > select App in the Air from the list and click Cancel.
Only you can initiate a refund in the Apple ecosystem. Here's a guide: https://support.apple.com/en-us/HT204084
Go to the Play Store app > left menu > select Subscriptions > select App in the Air > cancel your subscription.
Refund: send your purchase ID (in an email from Google, starting with GPA…) to support via the feedback option in the app settings.
Samsung Galaxy Apps
Go to Galaxy Store > My Page > Receipts > Select App in the Air > tap Unsubscribe.
You can make a refund here. Follow this link and open the "1:1 inquiry" tab > select Galaxy Store service > enter your email > request type - "Purchase/Return" > enter all fields > recommended reason for return - "Accidental purchase" (in the "Details" field).
We'd like to know why you decided to abandon the app. To share your thoughts, contact our support team via the feedback option in the app settings. We'd love to hear your feedback and help you if you have any questions or concerns.