There are a couple reasons why you may not be able to see a newly added column to a table in your Qrimp app.
First reason, some apps may have a setting that only shows 10 columns at a time in the grid view.
To see more columns, go to Design > Form Designer. Click "Edit Column Labels" in the right hand column. Click on the "N" in the "Hide In Table" column for the column you wish to show.
Return to your table to see your column.
The second reason your column may not appear would be due to
Column Security being enabled on the Table. When column security is enabled, you'll see a message at the top of the table description after you add the column letting you know that you'll need to configure column security to enable users of the system to see the column you just added. In that message is a link to configure column security.
If you miss the link, you can easily get to the column security configuration page by hovering over Develop, clicking Table Management. Then find the table you added the column to and click the Column Security link for that table. You'll notice on the configuration page that appears that the checkboxes for the new field are all empty for all the groups. Click the checkboxes for the groups you'd like to see the column. Your changes are saved automatically.