Yes, Casetext has a citator! Like Lexis' Shepard's and Westlaw's KeyCite, Casetext's citator, called "SmartCite," uses a system of flags to indicate the treatment of cases.
However, SmartCite is more than just flags. SmartCite is a collection of features that help you evaluate whether a case is good law and find other relevant cases citing that opinion.
It has two overarching objectives: (1) to alert you to bad law, and (2) to alert you to other cases that you should read before deciding whether to rely on a case.
To learn how to use SmartCite to determine whether a case is good law, please see the following article: https://help.casetext.com/articles/2122319-how-do-i-know-if-a-case-is-still-good-law
To learn how to use SmartCite to see how a case has been treated on appeal, please see the following article: https://help.casetext.com/articles/2947781-can-i-see-how-a-case-has-been-treated-on-appeal
To learn how to use SmartCite to to see how a case has been cited by other cases, please see the following article: https://help.casetext.com/articles/2946573-can-i-see-how-a-case-has-been-cited-by-other-cases
*Shepard's and KeyCite are trademarks and intellectual property of LexisNexis and Thomson Reuters, respectively. Please note that Casetext is not affiliated with LexisNexis or Westlaw.