If you switched from an iPhone to an Android, or vice versa, you may run into issues when signing into RoboKiller. The reason for this is because the subscription is tied to your Apple ID, or Google Account, respectively and each platform is separate from the other. Since Apple and Google don't give developers access to payments, we aren't able to update subscriptions ourselves, and you will need to cancel your original subscription and resubscribe on the new device.
When you switch from an iPhone to an iPhone or an Android to another Android, you can automatically restore your account. All you need to do is reinstall the application on your new device and tap on the RESTORE PURCHASE button on the payment screen.