Numbers is now free on iOS 7 and can read/write XLS and XLSX out of the box. The iOS7 version is definitely a step-up from previous versions. Why would someone make the $10 purchase for the IAP (required for export) rather than use Numbers?
Perhaps the biggest difference between Permanent and Numbers is the interface. It's easy to suggest that tablet spreadsheets might all work the same, but if you try a few you'll find they are widely different experiences.
Permanent has cloud support for Box and Dropbox. Numbers supports only iCloud.
Permanent is free, and most people do fine with the free version, so a pro upgrade is generally not required to use the app.
FYI Numbers supports both box and dropbox (via "open in another app"). For example, to upload to box:
- hit the share button (the box with the up arrow)
- "Open in Another App"
- Choose format (e.g. Excel or CSV)
- Hit "Choose App"
- Hit "Open in Box"
[now the box app opens]
- Hit "Upload"However it doesn't read or write ODF/ODS files which is a pain for me at least.
With a little time and gnireenigne, anything's possible ;)
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