Raylex® is a free Android app developed by Oystershell under the category of Education & Reference. This app is designed to help people quit their habit of nail-biting. The app comes with a set of features that are aimed at providing reminders, handy tips, and motivation to help users quit nail-biting.

The app is designed to work together with the Raylex® pen, which is sold separately. The app reminds users to apply Raylex®, provides useful tips to quit nail-biting, and motivates users by reminding them of the rewards they can expect. Raylex® claims that with the help of this app and the Raylex® pen, users can successfully quit nail-biting in just 18 days.

Overall, the Raylex® app is a useful tool for those who are struggling to quit the habit of nail-biting. The app is easy to use, comes with a set of handy features, and is completely free to download.