Which architecture design is better using SQL Server, Api Rest and Redis Cache

My solution has a web application and a mobile application that consume data from an Api Rest and the Api Rest requests the data from a SQL Server database. To improve performance we have several approaches.

1. Use Redis Cache as a proxy between our Api Rest and SQL Server
2. Use Redis Cache as a proxy between our web application and the Api Rest (what would happen with the mobile application?)

Which solution is better?

*Redis cache would be used to store the most common requests