The countdown began some time ago, but now we’re on the threshold. As of tomorrow, Twitter will no longer allow 3rd party applications or sites to access your Twitter account via a typical username/password (basic) authorization. From that point forward, all 3rd party authorization must happen via OAuth.

OAuth (open authorization) is a way to let 3rd party sites have access to your Twitter information without ever having to input your username or password. The idea, of course, is safer keeping of your user credentials, without having to be concerned about a lack of resources shared.

Most applications, by now, have implemented OAuth. However, it’s worth a check through whatever you use through Twitter to make certain that its not using basic authorization so that you’ll have this last day to find an alternative.

Read next: Take your Monday anger out on pigs. The great Angry Birds for iPhone updated.