How many pictures?

In 1999, the peak of the film-camera industry, consumers took around 80bn photos (according to Kodak). We're taking far more now, but how many more?

No-one can know this exactly, but there are some points of triangulation:

• Facebook said in May 2015 that two billion photos are shared on its systems every day, by 1.4bn users  - a 730bn/year run-rate.
• This does not include WhatsApp, which in April 2014 it said it was seeing 700m photos a day from 500m users (255bn a year) - it seems pretty likely that that number has risen since. 
• Snapchat gave a number of 700m a day, back in May 2014 - again, that will have risen (a lot) since. 

Just rounding WhatsApp and Snapchat up to 1bn/day to account for growth in the last year (WhatsApp has grown to over 700m users) and presuming no growth at Facebook this year gets us to a figure of 1.5 trillion photos shared this year. Growth in usage in the year across these could easily take that to over 2 trillion. That presumes no duplication between these three networks, which is not certain but might not be enormous. 

That, though, only gets us so far: Facebook, Instagram, WhatsApp and Snapchat are not everything. There are dozens of other smaller messaging apps with tens of millions of users, and also Apple's iMessage, which is the dark matter of social, but there's also WeChat, which has close to 600m active users and has not given a figure for photos shared (that I can find, of course). 

Usage patterns are not the same across all these networks (Facebook's asymmetric sharing of albums of images or Snapchats 'picture as message'  are not the same in WeChat). But simply looking at scale, it seems likely that all these other networks could easily be adding another 500bn images this year, and possibly much more. 

Hence, at least 2 trillion photos will be shared this year, and possibly 3 trillion or more. Spread across roughly 2bn smartphone users, that's only 2-3 photos per day per person, which is not so extraordinary, and of course use is not actually spread evenly, so there's room in that number for some people to be sharing lots and others none.  

That's just how many photos were shared, though. How many more were taken and not shared? Again, there's no solid data for this (though Apple and Google probably have some). Some image sharing is probably 1:1 for taken:shared (Snapchat, perhaps) but other people on other services will take hundreds and share only a few. So it could be double the number of photos shared or it could be 10x. Meanwhile, estimates of the total number of photos ever taken on film range from 2.5-3.5 trillion. That in turn would suggest that more photos will be taken this year than were taken on film in the entire history of the analogue camera business. 

Footnote: in passing, this is a discussion of how one can try to reach approximate estimates in the absence of solid data. On that theme I also wrote a long post discussing where mobile statistics come from here.