iOS apps closes right after launch

Question

I created and install several iOS apps using Xcode , it worked fine , but in a few days I tried to launch some of them. I tried to launch an app, It showed launch screen and

Answer 1

You don't have a paid developer account, do you?

If you have the free developer account, the certificate will stay valid only seven days. That's why you have to reinstall you apps every 7 days on your devices.