I just pushed a fix to the hated ‘unknown error’ bugs that have been plaguing a minority of Simple Check-in users. This fix is available in versions 1.3 and above.

The error was due to number formatting differences between US and European devices.

For future reference, on many european Locale phones, formatting a string with the double 46.1234 will actually be written out as 46,1234. See the difference? The european formatting uses a comma instead of the US-standard decimal place.

This caused errors when calling the foursquare API as this is not a valid way to represent Lat/Long coordinates.

So if you were frustrated because Simple Check-in wasn’t working for you then download the new version and give it a try!