Is Bubble a mobile app?

Could you please clarify for me if Bubble is indeed a mobile application? I've heard some discussions about it, but I'm still not entirely sure. Is it designed specifically for smartphones and tablets, or does it have a different platform? Could you elaborate on its functionalities and features, if it is indeed a mobile app? Additionally, is it available on both iOS and Android devices, or is it limited to a specific operating system? Your insights would be greatly appreciated.