@Seed,
iOS is more secure as compared to the Android reason because iOS is based on a closed source platform whereas Android is based on the open source platform.
iOS app releases first compared to the Android app reason because iOS is based on C++/Swift language (less coding is required) whereas Android is based on the Java (a large piece of coding is required).
iOS apps are more profitable because it's major market share is in the US & UK whereas Android market share is in Asia. Due to the difference between the per capita income of both continents iOS app generates more revenue.
