Ofcourse many tools you have I use for IOS our ASO Tool - http://asktolik.com/aso and it's free , also popular sensor tower too, for android you have less tools and more can work with google planner tool. If you intersting learn more i share with you link my ASO course for beginners in udemy - https://www.udemy.com/app-store-optimization-aso-for-ios-no-marketing-2015/?couponCode=ASOGroup9$

Find good people and make test oh honest time to time and the honest guys give the power manage your business , if you feel somebody will steal from you and it's not heppend yet it's also problem

I can guide how sell all , and share with you my the sites i use and even connect you with some investor who buy from me app and maybe intersting in yours.