What is Follow Cost?
Follow Cost is a interesting and powerful statistic that helps you check the “cost” you would incur by “following” a person on twitter. This is a very useful statistic that I think every twitter client should adopt. Tweetie for iPhone was the first to implement follow cost and I use this feature of tweetie to check whether a follower is “worth the pain” (as follow cost puts it).
In short, Follow Cost gives you an approximate count of the number of updates a person tweets in a day. As a thumb rule, I don’t follow anyone with a follow cost of over 40. A celebrity with a high follow cost is @guykawasaki. (80+ at the time of this writing) His tweets are interesting, but is it worth the pain? Depends. To me, definitely not.
The API
Follow Cost has a relatively simple API. But unfortunately, even after 3 months of Tweetie 2 launch, no other twitter client has implemented. You just have to make a GET request to followcost.com server with the twitter username as follows.=
http://followcost.com/<username>.json
The resulting output is a json formatted string which can be parsed using any JSON Framework.
Objective C Code
To make life easier, I wrote a helper class MKFollowCost. To use the class, first download the JSON framework and follow their installation instructions. If you are writing a twitter client, chances are that, you would probably have done this. Download the code from below and drag the two files, MKFollowCost.h and MKFollowCost.m into your project.
You can instantiate a followcost object by
MKFollowCost *followCost = [[MKFollowCost alloc] initWithTwitterName:@"mugunthkumar"];
All of the variables like, milliscobles, tweets per day etc, can be accessed from this object. The object is designed to be embedded without your Twitter Profile object.
Downloads
FollowCost Objective C Wrapper: FollowCost v1.0
Rights
You can use it in your own Twitter client, royalty free. Attributing me is upto you. However, if you modify the source code, please make it open source.
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