Custom App compatibility with ERPNext newer versions

I have two questions.

  1. If I have the custom app in my pen drive. How to add it in the frappe-bench/apps. will simply coping the app into the frappe-bench/apps folder and running the command " bench --site testsite install-app erpnext " do the magic?

  2. If at the time when I added the custom app ERPNext version was ERPNextV6. Will the app be still compatible with ERPNextV7


1.As long as the app doesn’t exist already, you can install the app you’ve copied.
2. It should be compatible, but can’t say completely for sure because it depends on your code.

@vjFaLk Thanks