Is Viber suitable for international communication, and what are its drawbacks?
Viber 是否适合国际通信，有哪些缺点？
Viber offers free international calls and messaging but may have a smaller user base compared to other messaging apps and could be affected by internet connectivity.
Viber 提供免费的国际通话和信息服务，但与其他信息应用程序相比，其用户群可能较小，并可能受到互联网连接的影响。