My favorite anti-suicide advice is 'Never commit suicide when hungover'. It sounds subversive but I think it gets the message across by first not discounting th

My favorite anti-suicide advice is 'Never commit suicide when hungover'. It sounds subversive but I think it gets the message across by first not discounting that the other person may have valid and important problems, and then emphasizing that all states of mind are subject to improvement. You could (carefully) curate a list of this sort of advice from people who have actually felt suicidal at one point or another and pop up a random message on demand in the app. Carefully, as most cheerful advice does not sound so good when you are depressed.