When contemplating the purchase of a smartphone, what uses of the phone would cause one to need 16GB vs 32GB vs 64GB?

It depends on the amount of data and app you want to download.

I’ve personally found that the largest uses of storage are the documents and files, not the apps. By combining all of videos that you take with your device, it can add up to several gigabytes of data. Audio files and songs take up a lot of space.

If you plan on using the device as a permanent storage location for larges amounts of videos, presentations, audio files, and the like, then you should get a device with a large amount of storage.

If you plan on deleting / transferring any data off the device that you don’t actually need on the device, then 16G is enough (that’s what I’m using right now).

Watching lots of videos like HD Pornos or an even bigger collection of pirated music.

I have a large music collection (just under 28 GB), and a few videos and pictures, plus some apps. It’s a good thing I don’t take my entire music library with me, so I can do fine on 24 GB (8 GB internal + 16 GB SD card), but 16 GB would be hard and 8 GB would be impossible. Fortunately, I went Android, so I can add storage; Apple doesn’t allow that :p

BTW, video (especially HD video) takes up a lot of space. If you want to watch movies, 16 GB won’t really cut it.

Media storage in general: Videos, Music and Photos (pretty much in that descending order) are storage hogs. I don’t think that “Apps” in general will take a lot of storage space.

@CWOTUS I guess you noticed my lack of pluralization

But anyway, videos of any considerable length (more than a few minutes) can easily eat up hundreds of megabytes per video.

I confess that I hadn’t read your original excellent response, @PhiNotPi, or I probably would have forgone my own.

I have a 32gig iPhone. I didn’t think I would use it all but when I transferred my favorite music, one or two movies, audio books, ebooks, I am down to 5 gig available. I love the photo apps, there are so many editing that are so much fun. I also have a few drawing apps so the works of art I create with those apps take up a lot of space too. And of course the games, I have backgammon,a Hoyle card game app and about 20 others that I play regularly.

So I would advise get as much storage as you can afford because I am sure you will use it at some point in time!

I barely use the 8 or so I have on my phone.

Several friends of mine store their music on theirs (I have a separate iPod and I use spotify on my phone).