GroupMe is a group chat app aimed at groups such as friends, clubs, schools and non-profit organisations. Users create groups and exchange messages, and the service is available through the Apple App Store and Google Play. It is a consumer service and is not open source.
GroupMe is provided by Microsoft Corporation, based in Redmond in the United States, and therefore falls under US jurisdiction, including the CLOUD Act. The Microsoft services agreement places GroupMe in the same section as Skype and Teams and notes that GroupMe uses a US-based number for each group; the contracting party is Microsoft Corporation. According to the Microsoft privacy statement, data is stored in your region or in the United States; a GroupMe-specific storage location is not published. For people in the EEA, Microsoft Ireland Operations Limited is also a data controller, and Microsoft uses standard contractual clauses for transfers. For European organisations, a US consumer chat service rarely suits business or sensitive communication.