CallYa Flex is a free Android app developed by Vodafone GmbH, falling under the Utilities & Tools category. With this app, you can create your own personalized mobile plan that suits your needs, deciding on how many high-speed MBs or minutes and SMS you need every month.

The app offers an overview of your current balance and remaining units on the home page, and you can refill units anytime by clicking on the plus sign. The use overview allows you to see your data and unit consumption for the last 4 weeks in detail or in aggregate for the past 3 months. You can also use the app to load your card balance, transfer funds to others, or request funds. The expenditure table lets you view your current and past issues in detail for the last 4 weeks or in aggregate for the past 3 months.

Overall, CallYa Flex is a user-friendly app that offers flexibility and control over your mobile plan, making it a great choice for those who want to customize their plan according to their needs.