1.Develop more than three App use same data and framework, just change UI and Publisher.They have 3 different Profit model.
The first is for absolutely free. The second is AD model. The third is paid download.
2.Use less online service, api, or any remote request. The less the better.
3.Find one or more partner develop android.And not all app need android version.
4.I go out to work to make money and then hire someone to do it, or do it myself, need think and calculate.