This consideration is not just for Mobile apps, and Web apps could benefit from it too. The idea is to reduce the load on your backend server, by caching frequently requested data, that doesn’t change much, on the middle tier and eliminate querying the database too frequently. For example, the catalog of products a company is selling is not likely to change during the day. So instead of executing a query for all the products in your database for each customer that access your application, execute the query once per day, cache the data in the middle tier, and return this cached data to every customer.