Thanks, but what I’m really looking for is insights around the data transport, although I do understand what you’re saying about using a third-party service like Twitter. Perhaps there are services already designed for such stuff?

(BTW, this has absolutely NOTHING to do with things like free food offers. It’s just an example I came up with that has similar dynamics to the actual problem I’m addressing.)

So we could broadcast each announcement message to everybody (all current listeners) in real-time (like what Twitter would do) and let the client-side filter out the irrelevant messages (around 99.99%).

Or we could reduce that bandwidth by having clients update the server periodically (eg., every 5 minutes) with their location, then for each announcement, a server would locate clients within a reasonable radius based on their last reported position and only notify them directly through a push notification of some sort; the clients would still do some filtering, but this would reduce incoming traffic considerably.

I’m not sure which is worse: a server updating a huge number of clients in near real-time, or a huge number of clients updating the server with their geographical location every 5 minutes or so.

Or, an alternative is for the clients to poll the server every 15-30 seconds, but this seems even worse in terms of traffic. (Althought this approach is probably ok if we used an existing platform like Twitter.)

Are these sorts of concerns things that anybody even worries about these days? (Ie., that bandwidth is becoming so cheap and plentiful that it’s just not much of a concern down the road.)

-David 

On Jul 30, 2014, at 5:51 AM, Stephen Partington <cryptworks@gmail.com> wrote:

Well you will need to tag your content for preferences. On account creation you do a questionnaire. So that is now in a database. The you tie your app into the location services. That would ping back and everything in "range" would be tagged and made available in the apps offer screen. With a single notification of offers in your area. I would not suggest using another service as your transport as that can get your Data banned.