Apple has a habit of sometimes rewriting one of its apps from the ground up, for reasons that aren't immediately obvious. This usually comes with a drastic reduction of features in the rewritten app, much to the chagrin of its users, before they gradually start adding features back in. The Keynote apps (for Mac and iOS) recently went through this cycle as well.
When Keynote 2 for iOS came out, I found that not only was it missing a few (mostly minor) features, but most of all, it stopped working with the Satechi Bluetooth Remote. After some failed experiments, I decided to continue using the old app (version 1.7.2) for as long as possible.
Recently, though, the old version started popping up annoying notices that the presentation had changed, often multiple times. My guess is that this has something to do with behind-the-scenes changes in iCloud and iCloud Drive. In any case, it motivated me to try out the current versions of Keynote, both on iOS and on the Mac, again.
In short: Keynote 2.5 for iOS works with the Satechi Remote, which for me is the most important feature. The corresponding Keynote version 6.5 on the Mac seems to have moved a few things around compared to the older version, but I didn't miss any features.
I've been through my usual routine (design on the Mac, run from the iPad) for a presentation now and pretty much everything worked smoothly.
The only minor problem I noticed is that navigating the slides with the Satechi Remote now always produces an audible "click" noise on the iPad and there doesn't seem to be a way to switch that off other than to turn down the volume. You'll have to keep that in mind when using video and/or audio in a presentation, i.e. you'll have to mute/unmute the sound at the right moment.
Another difference I noticed in the Mac version is the way in how it exports presenter notes to PDF. In previous versions, it put them below the slides, so that you could publish your slides with "subtitles" (example). Now when you choose to include your presenter notes in the PDF, Keynote creates a page that looks more like a document - with the slide on top, the notes below it and lots of whitespace around them. This format is not great if you want to publish your slides on Slideshare. I'm currently experimenting with other ways to include the presenter notes (which are often essential when you're using a more visual presentation style) - expect a separate article about that soon.
If you've been holding out on upgrading to the current Keynote versions (and I know some fellow presenters who did), you may want to take a look again now. I still have a copy of the old iOS app, just in case, but I don't think I'll be needing it.
(Photo: Yours truly, setting up the iPad with the Satechi Remote to give a presentation)
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