How do adults find happiness in life?

Outdoor hobbies. I've got really into foraging, which has multiple benefits, I get to be outside, I get exercise, I learn new things which stimulates my brain, and if I'm lucky I also get free food (which is usually superior in taste and nutrition to store bought). I combine it with hiking, fishing, geocaching etc and if I'm alone I sometimes listen to music on my headphones. Once you start developing outdoor hobbies it's like you unlock an insanely intricate open world video game.

I just recently quit my job and it's got me thinking about app development around this idea.