1 Report Overview 1.1 Study Scope 1.2 Market Analysis by Type 1.2.1 Global Video Call Software Market Size Growth Rate by Type: 2016 VS 2021 VS 2027 1.2.2 PC 1.2.3 Mobile 1.3 Market by Application 1.3.1 Global Video Call Software Market Share by Application: 2016 VS 2021 VS 2027 1.3.2 Personal Use 1.3.3 Enterprise Commercial 1.3.4 Other 1.4 Study Objectives 1.5 Years Considered 2 Global Growth Trends 2.1 Global Video Call Software Market Perspective (2016-2027) 2.2 Video Call Software Growth Trends by Regions 2.2.1 Video Call Software Market Size by Regions: 2016 VS 2021 VS 2027 2.2.2 Video Call Software Historic Market Share by Regions (2016-2021) 2.2.3 Video Call Software Forecasted Market Size by Regions (2022-2027) 2.3 Video Call Software Industry Dynamic 2.3.1 Video Call Software Market Trends 2.3.2 Video Call Software Market Drivers 2.3.3 Video Call Software Market Challenges 2.3.4 Video Call Software Market Restraints 3 Competition Landscape by Key Players 3.1 Global Top Video Call Software Players by Revenue 3.1.1 Global Top Video Call Software Players by Revenue (2016-2021) 3.1.2 Global Video Call Software Revenue Market Share by Players (2016-2021) 3.2 Global Video Call Software Market Share by Company Type (Tier 1, Tier 2 and Tier 3) 3.3 Players Covered: Ranking by Video Call Software Revenue 3.4 Global Video Call Software Market Concentration Ratio 3.4.1 Global Video Call Software Market Concentration Ratio (CR5 and HHI) 3.4.2 Global Top 10 and Top 5 Companies by Video Call Software Revenue in 2020 3.5 Video Call Software Key Players Head office and Area Served 3.6 Key Players Video Call Software Product Solution and Service 3.7 Date of Enter into Video Call Software Market 3.8 Mergers & Acquisitions, Expansion Plans 4 Video Call Software Breakdown Data by Type 4.1 Global Video Call Software Historic Market Size by Type (2016-2021) 4.2 Global Video Call Software Forecasted Market Size by Type (2022-2027) 5 Video Call Software Breakdown Data by Application 5.1 Global Video Call Software Historic Market Size by Application (2016-2021) 5.2 Global Video Call Software Forecasted Market Size by Application (2022-2027) 6 North America 6.1 North America Video Call Software Market Size (2016-2027) 6.2 North America Video Call Software Market Size by Type 6.2.1 North America Video Call Software Market Size by Type (2016-2021) 6.2.2 North America Video Call Software Market Size by Type (2022-2027) 6.2.3 North America Video Call Software Market Size by Type (2016-2027) 6.3 North America Video Call Software Market Size by Application 6.3.1 North America Video Call Software Market Size by Application (2016-2021) 6.3.2 North America Video Call Software Market Size by Application (2022-2027) 6.3.3 North America Video Call Software Market Size by Application (2016-2027) 6.4 North America Video Call Software Market Size by Country 6.4.1 North America Video Call Software Market Size by Country (2016-2021) 6.4.2 North America Video Call Software Market Size by Country (2022-2027) 6.4.3 United States 6.4.4 Canada 7 Europe 7.1 Europe Video Call Software Market Size (2016-2027) 7.2 Europe Video Call Software Market Size by Type 7.2.1 Europe Video Call Software Market Size by Type (2016-2021) 7.2.2 Europe Video Call Software Market Size by Type (2022-2027) 7.2.3 Europe Video Call Software Market Size by Type (2016-2027) 7.3 Europe Video Call Software Market Size by Application 7.3.1 Europe Video Call Software Market Size by Application (2016-2021) 7.3.2 Europe Video Call Software Market Size by Application (2022-2027) 7.3.3 Europe Video Call Software Market Size by Application (2016-2027) 7.4 Europe Video Call Software Market Size by Country 7.4.1 Europe Video Call Software Market Size by Country (2016-2021) 7.4.2 Europe Video Call Software Market Size by Country (2022-2027) 7.4.3 Germany 7.4.4 France 7.4.5 U.K. 7.4.6 Italy 7.4.7 Russia 7.4.8 Nordic 8 Asia-Pacific 8.1 Asia-Pacific Video Call Software Market Size (2016-2027) 8.2 Asia-Pacific Video Call Software Market Size by Type 8.2.1 Asia-Pacific Video Call Software Market Size by Type (2016-2021) 8.2.2 Asia-Pacific Video Call Software Market Size by Type (2022-2027) 8.2.3 Asia-Pacific Video Call Software Market Size by Type (2016-2027) 8.3 Asia-Pacific Video Call Software Market Size by Application 8.3.1 Asia-Pacific Video Call Software Market Size by Application (2016-2021) 8.3.2 Asia-Pacific Video Call Software Market Size by Application (2022-2027) 8.3.3 Asia-Pacific Video Call Software Market Size by Application (2016-2027) 8.4 Asia-Pacific Video Call Software Market Size by Region 8.4.1 Asia-Pacific Video Call Software Market Size by Region (2016-2021) 8.4.2 Asia-Pacific Video Call Software Market Size by Region (2022-2027) 8.4.3 China 8.4.4 Japan 8.4.5 South Korea 8.4.6 Southeast Asia 8.4.7 India 8.4.8 Australia 9 Latin America 9.1 Latin America Video Call Software Market Size (2016-2027) 9.2 Latin America Video Call Software Market Size by Type 9.2.1 Latin America Video Call Software Market Size by Type (2016-2021) 9.2.2 Latin America Video Call Software Market Size by Type (2022-2027) 9.2.3 Latin America Video Call Software Market Size by Type (2016-2027) 9.3 Latin America Video Call Software Market Size by Application 9.3.1 Latin America Video Call Software Market Size by Application (2016-2021) 9.3.2 Latin America Video Call Software Market Size by Application (2022-2027) 9.3.3 Latin America Video Call Software Market Size by Application (2016-2027) 9.4 Latin America Video Call Software Market Size by Country 9.4.1 Latin America Video Call Software Market Size by Country (2016-2021) 9.4.2 Latin America Video Call Software Market Size by Country (2022-2027) 9.4.3 Mexico 9.4.4 Brazil 10 Middle East & Africa 10.1 Middle East & Africa Video Call Software Market Size (2016-2027) 10.2 Middle East & Africa Video Call Software Market Size by Type 10.2.1 Middle East & Africa Video Call Software Market Size by Type (2016-2021) 10.2.2 Middle East & Africa Video Call Software Market Size by Type (2022-2027) 10.2.3 Middle East & Africa Video Call Software Market Size by Type (2016-2027) 10.3 Middle East & Africa Video Call Software Market Size by Application 10.3.1 Middle East & Africa Video Call Software Market Size by Application (2016-2021) 10.3.2 Middle East & Africa Video Call Software Market Size by Application (2022-2027) 10.3.3 Middle East & Africa Video Call Software Market Size by Application (2016-2027) 10.4 Middle East & Africa Video Call Software Market Size by Country 10.4.1 Middle East & Africa Video Call Software Market Size by Country (2016-2021) 10.4.2 Middle East & Africa Video Call Software Market Size by Country (2022-2027) 10.4.3 Turkey 10.4.4 Saudi Arabia 10.4.5 UAE 11 Key Players Profiles 11.1 Skype 11.1.1 Skype Company Details 11.1.2 Skype Business Overview 11.1.3 Skype Video Call Software Introduction 11.1.4 Skype Revenue in Video Call Software Business (2016-2021) 11.1.5 Skype Recent Development 11.2 Jus Talk 11.2.1 Jus Talk Company Details 11.2.2 Jus Talk Business Overview 11.2.3 Jus Talk Video Call Software Introduction 11.2.4 Jus Talk Revenue in Video Call Software Business (2016-2021) 11.2.5 Jus Talk Recent Development 11.3 Zoom Meeting 11.3.1 Zoom Meeting Company Details 11.3.2 Zoom Meeting Business Overview 11.3.3 Zoom Meeting Video Call Software Introduction 11.3.4 Zoom Meeting Revenue in Video Call Software Business (2016-2021) 11.3.5 Zoom Meeting Recent Development 11.4 Google Duo 11.4.1 Google Duo Company Details 11.4.2 Google Duo Business Overview 11.4.3 Google Duo Video Call Software Introduction 11.4.4 Google Duo Revenue in Video Call Software Business (2016-2021) 11.4.5 Google Duo Recent Development 11.5 Discord 11.5.1 Discord Company Details 11.5.2 Discord Business Overview 11.5.3 Discord Video Call Software Introduction 11.5.4 Discord Revenue in Video Call Software Business (2016-2021) 11.5.5 Discord Recent Development 11.6 FaceTime 11.6.1 FaceTime Company Details 11.6.2 FaceTime Business Overview 11.6.3 FaceTime Video Call Software Introduction 11.6.4 FaceTime Revenue in Video Call Software Business (2016-2021) 11.6.5 FaceTime Recent Development 11.7 Facebook Messenger 11.7.1 Facebook Messenger Company Details 11.7.2 Facebook Messenger Business Overview 11.7.3 Facebook Messenger Video Call Software Introduction 11.7.4 Facebook Messenger Revenue in Video Call Software Business (2016-2021) 11.7.5 Facebook Messenger Recent Development 11.8 WeChat 11.8.1 WeChat Company Details 11.8.2 WeChat Business Overview 11.8.3 WeChat Video Call Software Introduction 11.8.4 WeChat Revenue in Video Call Software Business (2016-2021) 11.8.5 WeChat Recent Development 11.9 Microsoft Teams 11.9.1 Microsoft Teams Company Details 11.9.2 Microsoft Teams Business Overview 11.9.3 Microsoft Teams Video Call Software Introduction 11.9.4 Microsoft Teams Revenue in Video Call Software Business (2016-2021) 11.9.5 Microsoft Teams Recent Development 11.10 LINE 11.10.1 LINE Company Details 11.10.2 LINE Business Overview 11.10.3 LINE Video Call Software Introduction 11.10.4 LINE Revenue in Video Call Software Business (2016-2021) 11.10.5 LINE Recent Development 11.11 Viber 11.11.1 Viber Company Details 11.11.2 Viber Business Overview 11.11.3 Viber Video Call Software Introduction 11.11.4 Viber Revenue in Video Call Software Business (2016-2021) 11.11.5 Viber Recent Development 11.12 Tango 11.12.1 Tango Company Details 11.12.2 Tango Business Overview 11.12.3 Tango Video Call Software Introduction 11.12.4 Tango Revenue in Video Call Software Business (2016-2021) 11.12.5 Tango Recent Development 12 Analyst's Viewpoints/Conclusions 13 Appendix 13.1 Research Methodology 13.1.1 Methodology/Research Approach 13.1.2 Data Source 13.2 Disclaimer 13.3 Author Details

List of Tables Table 1. Global Video Call Software Market Size Growth Rate by Type (US$ Million):2016 VS 2021 VS 2027 Table 2. Key Players of PC Table 3. Key Players of Mobile Table 4. Global Video Call Software Market Size Growth by Application (US$ Million): 2016 VS 2021 VS 2027 Table 5. Global Video Call Software Market Size by Regions (US$ Million): 2016 VS 2021 VS 2027 Table 6. Global Video Call Software Market Size by Regions (2016-2021) & (US$ Million) Table 7. Global Video Call Software Market Share by Regions (2016-2021) Table 8. Global Video Call Software Forecasted Market Size by Regions (2022-2027) & (US$ Million) Table 9. Global Video Call Software Market Share by Regions (2022-2027) Table 10. Video Call Software Market Trends Table 11. Video Call Software Market Drivers Table 12. Video Call Software Market Challenges Table 13. Video Call Software Market Restraints Table 14. Global Video Call Software Revenue by Players (2016-2021) & (US$ Million) Table 15. Global Video Call Software Market Share by Players (2016-2021) Table 16. Global Top Video Call Software Players by Company Type (Tier 1, Tier 2 and Tier 3) (based on the Revenue in Video Call Software as of 2020) Table 17. Ranking of Global Top Video Call Software Companies by Revenue (US$ Million) in 2020 Table 18. Global 5 Largest Players Market Share by Video Call Software Revenue (CR5 and HHI) & (2016-2021) Table 19. Key Players Headquarters and Area Served Table 20. Key Players Video Call Software Product Solution and Service Table 21. Date of Enter into Video Call Software Market Table 22. Mergers & Acquisitions, Expansion Plans Table 23. Global Video Call Software Market Size by Type (2016-2021) (US$ Million) Table 24. Global Video Call Software Revenue Market Share by Type (2016-2021) Table 25. Global Video Call Software Forecasted Market Size by Type (2022-2027) (US$ Million) Table 26. Global Video Call Software Revenue Market Share by Type (2022-2027) & (US$ Million) Table 27. Global Video Call Software Market Size Share by Application (2016-2021) & (US$ Million) Table 28. Global Video Call Software Revenue Market Share by Application (2016-2021) Table 29. Global Video Call Software Forecasted Market Size by Application (2022-2027) (US$ Million) Table 30. Global Video Call Software Revenue Market Share by Application (2022-2027) & (US$ Million) Table 31. North America Video Call Software Market Size by Type (2016-2021) (US$ Million) Table 32. North America Video Call Software Market Size by Type (2022-2027) & (US$ Million) Table 33. North America Video Call Software Market Size by Application (2016-2021) (US$ Million) Table 34. North America Video Call Software Market Size by Application (2022-2027) & (US$ Million) Table 35. North America Video Call Software Market Size by Country (2016-2021) & (US$ Million) Table 36. North America Video Call Software Market Size by Country (2022-2027) & (US$ Million) Table 37. Europe Video Call Software Market Size by Type (2016-2021) (US$ Million) Table 38. Europe Video Call Software Market Size by Type (2022-2027) & (US$ Million) Table 39. Europe Video Call Software Market Size by Application (2016-2021) (US$ Million) Table 40. Europe Video Call Software Market Size by Application (2022-2027) & (US$ Million) Table 41. Europe Video Call Software Market Size by Country (2016-2021) & (US$ Million) Table 42. Europe Video Call Software Market Size by Country (2022-2027) & (US$ Million) Table 43. Asia-Pacific Video Call Software Market Size by Type (2016-2021) (US$ Million) Table 44. Asia-Pacific Video Call Software Market Size by Type (2022-2027) & (US$ Million) Table 45. Asia-Pacific Video Call Software Market Size by Application (2016-2021) (US$ Million) Table 46. Asia-Pacific Video Call Software Market Size by Application (2022-2027) & (US$ Million) Table 47. Asia-Pacific Video Call Software Market Size by Region (2016-2021) & (US$ Million) Table 48. Asia-Pacific Video Call Software Market Size by Region (2022-2027) & (US$ Million) Table 49. Latin America Video Call Software Market Size by Type (2016-2021) (US$ Million) Table 50. Latin America Video Call Software Market Size by Type (2022-2027) & (US$ Million) Table 51. Latin America Video Call Software Market Size by Application (2016-2021) (US$ Million) Table 52. Latin America Video Call Software Market Size by Application (2022-2027) & (US$ Million) Table 53. Latin America Video Call Software Market Size by Country (2016-2021) & (US$ Million) Table 54. Latin America Video Call Software Market Size by Country (2022-2027) & (US$ Million) Table 55. Middle East & Africa Video Call Software Market Size by Type (2016-2021) (US$ Million) Table 56. Middle East & Africa Video Call Software Market Size by Type (2022-2027) & (US$ Million) Table 57. Middle East & Africa Video Call Software Market Size by Application (2016-2021) (US$ Million) Table 58. Middle East & Africa Video Call Software Market Size by Application (2022-2027) & (US$ Million) Table 59. Middle East & Africa Video Call Software Market Size by Country (2016-2021) & (US$ Million) Table 60. Middle East & Africa Video Call Software Market Size by Country (2022-2027) & (US$ Million) Table 61. Skype Company Details Table 62. Skype Business Overview Table 63. Skype Video Call Software Product Table 64. Skype Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 65. Skype Recent Development Table 66. Jus Talk Company Details Table 67. Jus Talk Business Overview Table 68. Jus Talk Video Call Software Product Table 69. Jus Talk Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 70. Jus Talk Recent Development Table 71. Zoom Meeting Company Details Table 72. Zoom Meeting Business Overview Table 73. Zoom Meeting Video Call Software Product Table 74. Zoom Meeting Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 75. Zoom Meeting Recent Development Table 76. Google Duo Company Details Table 77. Google Duo Business Overview Table 78. Google Duo Video Call Software Product Table 79. Google Duo Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 80. Google Duo Recent Development Table 81. Discord Company Details Table 82. Discord Business Overview Table 83. Discord Video Call Software Product Table 84. Discord Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 85. Discord Recent Development Table 86. FaceTime Company Details Table 87. FaceTime Business Overview Table 88. FaceTime Video Call Software Product Table 89. FaceTime Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 90. FaceTime Recent Development Table 91. Facebook Messenger Company Details Table 92. Facebook Messenger Business Overview Table 93. Facebook Messenger Video Call Software Product Table 94. Facebook Messenger Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 95. Facebook Messenger Recent Development Table 96. WeChat Company Details Table 97. WeChat Business Overview Table 98. WeChat Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 99. WeChat Recent Development Table 100. Microsoft Teams Company Details Table 101. Microsoft Teams Business Overview Table 102. Microsoft Teams Video Call Software Product Table 103. Microsoft Teams Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 104. Microsoft Teams Recent Development Table 105. LINE Company Details Table 106. LINE Business Overview Table 107. LINE Video Call Software Product Table 108. LINE Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 109. LINE Recent Development Table 110. Viber Company Details Table 111. Viber Business Overview Table 112. Viber Video Call Software Product Table 113. Viber Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 114. Viber Recent Development Table 115. Tango Company Details Table 116. Tango Business Overview Table 117. Tango Video Call Software Product Table 118. Tango Revenue in Video Call Software Business (2016-2021) & (US$ Million) Table 119. Tango Recent Development Table 120. Research Programs/Design for This Report Table 121. Key Data Information from Secondary Sources Table 122. Key Data Information from Primary Sources List of Figures Figure 1. Global Video Call Software Market Share by Type: 2020 VS 2027 Figure 2. PC Features Figure 3. Mobile Features Figure 4. Global Video Call Software Market Share by Application: 2020 VS 2027 Figure 5. Personal Use Case Studies Figure 6. Enterprise Commercial Case Studies Figure 7. Other Case Studies Figure 8. Video Call Software Report Years Considered Figure 9. Global Video Call Software Market Size (US$ Million), Year-over-Year: 2016-2027 Figure 10. Global Video Call Software Market Size (US$ Million), 2016 VS 2021 VS 2027 Figure 11. Global Video Call Software Market Share by Regions: 2020 VS 2027 Figure 12. Global Video Call Software Market Share by Regions (2022-2027) Figure 13. Global Video Call Software Market Share by Players in 2020 Figure 14. Global Top Video Call Software Players by Company Type (Tier 1, Tier 2 and Tier 3) (based on the Revenue in Video Call Software as of 2020 Figure 15. The Top 10 and 5 Players Market Share by Video Call Software Revenue in 2020 Figure 16. Global Video Call Software Revenue Market Share by Type (2016-2021) Figure 17. Global Video Call Software Revenue Market Share by Type (2022-2027) Figure 18. North America Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 19. North America Video Call Software Market Share by Type (2016-2027) Figure 20. North America Video Call Software Market Share by Application (2016-2027) Figure 21. North America Video Call Software Market Share by Country (2016-2027) Figure 22. United States Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 23. Canada Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 24. Europe Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 25. Europe Video Call Software Market Share by Type (2016-2027) Figure 26. Europe Video Call Software Market Share by Application (2016-2027) Figure 27. Europe Video Call Software Market Share by Country (2016-2027) Figure 28. Germany Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 29. France Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 30. U.K. Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 31. Italy Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 32. Russia Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 33. Nordic Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 34. Asia-Pacific Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 35. Asia-Pacific Video Call Software Market Share by Type (2016-2027) Figure 36. Asia-Pacific Video Call Software Market Share by Application (2016-2027) Figure 37. Asia-Pacific Video Call Software Market Share by Region (2016-2027) Figure 38. China Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 39. Japan Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 40. South Korea Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 41. Southeast Asia Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 42. India Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 43. Australia Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 44. Latin America Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 45. Latin America Video Call Software Market Share by Type (2016-2027) Figure 46. Latin America Video Call Software Market Share by Application (2016-2027) Figure 47. Latin America Video Call Software Market Share by Country (2016-2027) Figure 48. Mexico Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 49. Brazil Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 50. Middle East & Africa Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 51. Middle East & Africa Video Call Software Market Share by Type (2016-2027) Figure 52. Middle East & Africa Video Call Software Market Share by Application (2016-2027) Figure 53. Middle East & Africa Video Call Software Market Share by Country (2016-2027) Figure 54. Turkey Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 55. Saudi Arabia Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 56. UAE Video Call Software Market Size YoY Growth (2016-2027) & (US$ Million) Figure 57. Skype Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 58. Jus Talk Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 59. Zoom Meeting Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 60. Google Duo Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 61. Discord Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 62. FaceTime Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 63. Facebook Messenger Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 64. WeChat Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 65. Microsoft Teams Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 66. LINE Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 67. Viber Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 68. Tango Revenue Growth Rate in Video Call Software Business (2016-2021) Figure 69. Bottom-up and Top-down Approaches for This Report Figure 70. Data Triangulation Figure 71. Key Executives Interviewed

Skype Jus Talk Zoom Meeting Google Duo Discord FaceTime Facebook Messenger WeChat Microsoft Teams LINE Viber Tango