Update: I found a workaround. See below.
I have an iPhone 6 running iOS 8.3 and a rMBP running OS X 10.10.3.
Both machines have the latest version of Apple's Keynote app installed.
In the past, (i.e. on Mavericks) I could create an ad-hoc wireless network from my mac, connect to it using my iPhone, and control the presentation using Apple's Keynote app.
Unfortunately, with the advent of Yosemite, I find that the iOS Keynote app is now ridiculously flaky at connecting to Keynote through an ad-hoc network.
Any suggestions/fixes to this problem?
Thank you ahead of time!
Best Answer
If you think it's a discoveryd issue and 10.10.4 can't come too soon, might as well make it come now! Go to this Apple link and sign up for the public beta program, where you'll be given a link to download a piece of software that'll get the App Store to pick up beta updates. Take a backup of everything, install Beta Access Utility, and then install and enjoy a discoveryd-free Yosemite!