Using the Foursquare API for this sort of data aggregation service (i.e. for stalking people) has been done many times before. Unsurprisingly, Foursquare didn't like it one bit [0] and ended up changing their API to prevent this sort of usage [1].
Cool, it's good to know that foursquare is doing that.
Nevertheless, I think a better way for this app to perform is to wrap around foursquare. I'm already going to be checking-in with foursquare, so now I have to click a second button to check-in using Loca? If mfkp allows users to add their foursquare credentials, then it'll eliminate that extra step.
But I'm also not sure if mfkp is using a "check-in" model or what.
Nevertheless, I think a better way for this app to perform is to wrap around foursquare. I'm already going to be checking-in with foursquare, so now I have to click a second button to check-in using Loca? If mfkp allows users to add their foursquare credentials, then it'll eliminate that extra step.
But I'm also not sure if mfkp is using a "check-in" model or what.