QuickLinks -- Click here to rapidly navigate through this document

Exhibit 21.1

List of Subsidiaries as of December 31, 2015

Name of Subsidiary |  | Jurisdiction
--- | --- | ---
Advanced Wireless Group, LLC |  | Florida
Boingo Broadband, LLC. |  | California
Boingo Holding Participações, Ltda. |  | Brazil
Boingo UK Ltd. |  | England
Chicago Concourse Development Group, LLC |  | Delaware
Concourse Communications Baltimore, LLC |  | Delaware
Concourse Communications Canada, Inc. |  | Delaware
Concourse Communications Detroit, LLC |  | Delaware
Concourse Communications Group, LLC |  | Delaware
Concourse Communications Illinois, LLC |  | Illinois
Concourse Communications Minnesota, LLC |  | Delaware
Concourse Communications Nashville, LLC |  | Illinois
Concourse Communications Ottawa, LLC |  | Illinois
Concourse Communications Puerto Rico, LLC |  | Puerto Rico
Concourse Communications SSP, LLC |  | Delaware
Concourse Communications St. Louis, LLC |  | Delaware
Concourse Communications UK, Ltd. |  | England
Concourse Holding Co., Inc. |  | Delaware
Concourse Telecomunicacoes Brasil Ltda |  | Brazil
Electronic Media Systems, Inc. |  | Florida
Endeka Group, Inc. |  | California
InGate Holding, LLC |  | Illinois
InGate Technologies, LLC |  | Delaware
New York Telecom Partners, LLC |  | Delaware
Opti-Fi Networks, LLC |  | Delaware
tego Communications, Inc. |  | Delaware

QuickLinks

Exhibit 21.1

List of Subsidiaries as of December 31, 2015