Need help making an app for a depressed friend

Hey everyone. A friend of mine is struggling with depression and I thought of a simple app concept that may help him a bit. He has a hard time reaching out to people when he is feeling shitty, and I thought that maybe an app where you just press a button an immediately your friend/s get notified, without the anxiety that generates actually calling or texting someone to ask for help, as he has told me it happens to him all the time.

If anyone could guide me on how to do it or at least suggest a couple features, or even if you know of an app that can fulfill that purpose, that would be great.

Love you all and thanks in advance.