Other than analytics, what other ways to know whether an app feature is being used

I'm new to the community. Hoping to get some advice.

We rolled out an app 4 months ago, and wanted to find out which features from the app that are rarely or never used by the end user.

There are 5 main features, and only 2 have analytics in place.

I'm proposing to the team to conduct user survey, to find out what are the often, rarely, always and never used feature from the end users.

Is there other method that I can explore? other than conducting user survey?

Thank you!