I use DeckSet since a lot of years, I find it easy to use and I love the result. I don’t care about multi platform because I’m doing my presentation on a Mac. I don’t care paying fair prices to software.
The only downside I found was the lack of customization offered.
I’ll look into the GitHub list, especially to the 2 others macOS apps
> Multiple services on GitHub.com were affected by a network partition and subsequent database failure resulting in inconsistent information being presented on our website. Out of an abundance of caution we have taken steps to ensure the integrity of your data, including pausing webhook events and other internal processing systems.
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> Information displayed on GitHub.com is likely to appear out of date; however no data was lost. Once service is fully restored, everything should appear as expected. Further, this incident only impacted website metadata stored in our MySQL databases, such as issues and pull requests. Git repository data remains unaffected and has been available throughout the incident.