During the last night application Facebook for iOS was updated by the company of the same name and unfortunately the update generates functionality problems for a lot of people. A simple opening of the application generates its closure after a few seconds, but the good part is that you can solve the problem quite simply. By reinstalling the application via App Store you will bring it back to normal functionality and for now this is the only method by which I can have an application again Facebook usable, but only if you don't update it again. Those from Facebook have not made any announcement about the problem and if they are working on solving it, then we should see an update in the near future, but until then follow the advice above.
UPDATE: As an alternative to the above recommendation, if you have the old application saved in iTunes on PC/Mac, then delete the application from the terminal and install the old version (if it has not been updated) and then avoid installing the update available through the App Store.
