The problem with this is that there are literally millions of apps, the heart is a commonly-used symbol which can mean many things (there are a huge range of apps that use heart symbols, including obvious ones like health apps, the type of app you are worried about, but also to signify a "like" in many social media apps, and I've seen it used by message apps, radio stations, and sometimes just because the app developer likes the heart symbol or thinks it sets a nice image for their app or company even though it's nothing to do with the function). And it's almost impossible to search for these images. So unless you are very lucky and someone happens to have that same particular app the chances of anyone being able to identify it are very slim.
To me that looks like a fan rather than a radar sweep, but I don't know whether that will help you.
To be honest, your best bet is probably to ask her.