Hm, hard to say, on my Mac a few months ago I downloaded iStat Menus ($10 on the App Store) and I really enjoyed how detailed and customisable it was. Magnet is also one I enjoy using. Not sure on the iPhone though, I don't download many new apps on there.
You know you can get iStat server https://bjango.com/istatserver/ and then purchase the "ïStat View" App on your iDevice and remotely view all of the iStat Data from your Mac? I think this is pretty great.
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For the iPhone it has to be Headspace, Duolingo, Pocket, Scanbot, and Google Maps.
For the iPad Pro it's Procreate, Google Earth, GoodNotes, and Notability.
GoodNotes + Apple Pencil = Mind blown. I love taking hand written notes in lectures with GoodNotes. Excellent App.