I need the date when a cell is modified

[edikhsa]

I need the date when a cell is modified. The problem is that I cant use VBA, because I use the file in my smartphone with Google sheets as well which doesn't support VBA codes.
I am using the IF and NOW function, so when cell B1 is modified, A1 shows the current time (=IF(B1<>"",NOW(),"").
The problem is that whenever any other cell than B1 in the file is modified, excel automatically updates all cells, so the time in A1 updates to the current time, while I want A1 to keep the date when I modified the cell B1.
I know this is possible with VBA, But I cant use it as I said.
Any idea how I can get that date without updating conscientiously?
Thanks in advance,
Edris

 

[jorismoerings]

Hi,

If you want to this without VBA take a look at this : How to insert timestamps in excel sheet using formulas | Chandoo.org - Learn Microsoft Excel Online

 

[edikhsa]

Hi,

Thank you so much. This really worked out, however, Google Sheets doesn't support self-reference to a cell which is my problem