Somewhat ironically, now that I’m working full-time again, I’ve become quicker at responding to support email for personal apps. Not because I have more time (I don’t), but because of changes I’ve made out of necessity.
The biggest help has been setting up an online knowledge base. Now if a question comes in that isn’t documented, the response first gets added to the website, and then a link is sent to the user. Subsequent responses are much quicker now. Wish I would have done this years ago.