What is a saner specialty then? I’m getting tired of web dev because I’m getting too old to keep running on the treadmill. But what’s a better specialty (more

What is a saner specialty then? I’m getting tired of web dev because I’m getting too old to keep running on the treadmill. But what’s a better specialty (more stable, doesn’t change every week, large number of opportunities)? iOS or Android development? Something else?