I have to restart Apache every time I change my Rails code
Assuming you have to restart Apache even for model/view/controller code, it would seem as if you've set up Passenger to run your app in the production environment. You can fix this by appending RailsEnv development to your virtual host.
Some code will require you to restart the app--examples of this is anything in config/initializers and vendor.
There's a way to only restart the app (and not the entire server), which is simply touch tmp/restart.txt. This will update the timestamp of tmp/restart.txt, which will trigger Passenger to restart the app.
Additionally, you can do touch tmp/always_restart.txt. This will tell Passenger to restart the app on every page load. This can be useful if you're working on sections that require restarts (such as the examples mentioned above). To stop the automatic restarting, you'll have to delete the file, like this: rm tmp/always_restart.txt.
You can also use passenger by itself in development using the standalone mode. From your project directory, type
passenger start