Hybrid app development needs mostly only one code base for multiple platforms. A hybrid mobile app developer can build it once and then using a bridging technology such as PhoneGap, submit the app to all platforms (iPhone, Android, and Windows Phone.) Reach a wider audience by combining the best of both worlds.
Avoid the extra time developing the same app for each platform. Cross-platform apps can be immediately distributed between app stores as they are easier and faster to develop and deploy. Also skip the costs associated with developing two different versions for Android and iOS.