Twitterfon is one of my favourite applications for the iPhone (and iPod touch) however recently it has been crashing consistently everytime I start it up.
According to the Twitterfon website blog, the problem lies with Twitter.
Some users have been reporting me that TwitterFon crashes on launch. This has been happening since this afternoon. The root cause is that twitter has changed their JSON response which favorite status value is null instead of bool unexpectedly and randomly.
Not quite sure that that means as I am not really a techie, honestly!
However all is not lost.
If you apply this patch (and you may have to do it more than once) then it should fix the Twitterfon application until an update is released.