Hello,
I have experience in from scratch development of Android application,
including ones with sophisticated functionality and UI design, you can view one of my work at:
http://www.amazon.com/Denis-Manyukhin-Touch-Light-Trial/dp/B00RC4ODV4/ref=sr_1_36?s=mobile-apps&ie=UTF8&qid=1444143269&sr=1-36&keywords=touch+light
Please Before Accepting My Bid Contact Me with more information about app functionality you need
(freelancers can not contact you until your message them first), I can reduce the price taking in consideration that you are charity organization and depending on app's specification
Looking forward to hear from you,
Best regards,
Denis