You can cancel your subscription at any time. You will continue to have access to the premium features until the monthly subscription period expires.
1. Launch iOS Settings app
2. Scroll down to 'iTunes and App Store"
3. Tap Your Apple ID Email
4 Select 'View AppleID' (You may be asked to log in)
5. Tap 'Subscriptions'
6. Select the Insight Timer subscription
7. Tap 'Cancel Subscription' to disable it from auto-renewing at the end of the current billing cycle (monthly).
Google Play users:
1. Open the Google Play Store
2. Tap Menu (3 small horizontal lines) next to 'Google Play'.
3. Tap Account and then Subscriptions
4. Find the subscription you want to cancel
5. Tap Cancel