I have a few things to add to Matt Gemmell's analysis.
I trust Apple more than other companies. Apple's services… less so.
If the Mac's trajectory is being driven downwards, what about iOS? All the efforts put into iOS's development, are they bringing true progress or leading towards a reinvention of the wheel?
None of these apps is free, but they're all worth what little they cost.
Oh yes, it's very good.