As someone still becoming familiarized with everything that goes into the production stages of fonts, I'm realizing more and more that there's a lot that goes into turning a *typeface design* into a rock-solid *font* than I would've guessed when I started out. And yet, with everything I've learned, I still occasionally run into issues where my fonts don't always work as expected on different operating systems and apps. One of my deepest frustrations is the rapid pace that font support/expectations are evolving and, thus, what used to be correct is no longer the best thing to do.
So, I'm curious if anyone would be willing to share a thought or two about issues you've run into trying to make reliable fonts that work as cross-platform/app as needed and what you did about it. What tools do you find most useful and do you find that you become aware enough of what the tools help you with that you no longer need them?