Android method implementations for background service

Here's the situation.

I have an app with a database. The db must update every X minutes. The data is on a web server. The communication with the server will take about 10 httpget requests. So far accomplished a background service and a HTTPget function for getting the new information and updating the db. The problem is that it must update in background at that X minutes. I'm unsure what and how to realize that.

1.Use a delay function and run it at every X minutes ? 2.Use a sleep thread and wake it up at every X minutes ?

Or something else ?