The technology for mobile app development is quite different from general web development, there are three main kinds of mobile apps : Native apps, Hybrid apps, and Cross platform apps.
Native apps: They are written in the local environment of the Android or iOS operating system. And do not need any API to access them.
Hybrid apps: They are written using popular web technologies and then run on the devices using API. They use both local Android iOS environment and latest web technology, that’s why they are called Hybrid.
Cross platform apps: They are written using the latest frameworks, but are compiled into native applications to run on the device.