is there a way to save an app on one phone from another phone, maybe use a memory card

From which phone to which phone is a factor. As they may be on different Operating Systems then it wouldn't be compatible I would presume. So let me know which phone and model and we can then decide if it is indeed possible.

I know I can on my Windows Mobile 6 phone.  I don't know about your Android phone, though I would suspect so.

first... how do I save app to memory card

is it similar to a program on windows vista where only the .exe file can be saved, if so, how to find .exe file

Well, I presumed we were talking about an installer program.  If I download an application, then install it I have the original installation executable on my phone.  I can save that to my SD card (if I didn't already put it there when I downloaded it), then move that SD card to another phone and use it there.

I don't believe there is any way to copy an installed executable, unless it's somehow self-contained.  (a standalone .exe, or an .exe with all dependencies in the same folder).  As to locating the executable, that would depend on your OS and whether or not the application came pre-installed.  In a Windows phone, I'd look in the Program Files or Windows directories first.

thanks it works