storing data then alerting from stored data

I am needing some advice about the storing and reading of data provided by the user. I also need to have an alert/alarm that is set depending on the user input data.

I would like to know what would be the best way to store the data from the user so that my app can read the data and display it to the user. My app needs to be able to read the data and alert the user depending on the data the user provided.

Do I use a text file, XML file, SQLite? And which would work best for alerting the user?

 

So I have used SQLite to store the data. I have a save and load button and on asve the data is stored and on load the data is shown.

I however don't know how to make the data be displayed in a TextView box?

I also don't know how to store more than 1 item in my DB so the user may edit or delete later?

Any ideas how or links to explain?

Thanks