What are the limitations of HelloTalk?

Hello, could you elaborate on the limitations of HelloTalk as a language learning platform? Are there any specific areas where it falls short in comparison to other similar apps or traditional learning methods? Perhaps there are certain features or functionalities that users commonly complain about or find lacking. Additionally, are there any limitations related to the app's user base, such as a lack of diversity or engagement among users? I'd appreciate your insights on this topic.