TimeStamp when i edit

[Praveen2]

How to create new TimeStamp column when edit the form

[peterson]

In this situation I recommend you go to to your database and create a column called "last modified" or something like that. 
And in Appsheet in the expression formula use: NOW(), so, everytime someone updates this row this time will be changed and you'll have the date and time this row was last edited.

[Praveen2]

When I first enter the form, this column should not be displayed.

[peterson]

You can make this column be shown only in Detail view.

In the SHOW expression use the formula: CONTEXT("ViewType") <> "Form"