What is the best app for Microsoft Office

[KaskaA]

I am wondering what the best Microsoft Office app is. Cost isn't an issue, I'm looking for the app with the most functionality. If you can input equations in it that would be the best

 

[KaskaA]

Also, I should mention that I am looking for an app for a smartphone, but also would like to get a tablet in the near future, so I prefer like an app that works well on both, even though it's not necessary

 

[prjctchris]

Check out Docs to Go.

 

[Gekko]

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