Hey,

These are some of the top rated apps you may find to prepare for your civil services-

1. Unacademy
Unacademy is one of the largest online free learning initiatives in India. It is run by the civil services toppers who chose to leave the Indian Administrative Services and started providing guidance to the IAS aspirants

2.Mrunal
Mrunal Mobile App is providing valuable study material for IAS Exam through video lessons and linear format.

3. Civilsdaily
Civilsdaily Mobile App is providing comprehensive Current Affairs and News updates to help UPSC IAS aspirants to clear the UPSC IAS Exam

4. Iasbaba

5. The Hindu
The Hindu newspaper App is the most beneficial App for the quick look at the recent events of national and international importance.

6. VISION IAS

7. Insights On India

8. Clear IAS

9. AFEIAS(Academy For Excellence IAS)

10. Knowlez

Hope this helps.
Good luck!