Build and improve Android app

We want to improve our existing app which is partially complete We wanted to improve its UI and performance and want to add few features The app is use to send sms, manage sms history, manage contact and group list. List of work that needs to be done are Performance improvement including implementation of lazy loading and other. App should work when there are more than 5 to 10 thousands of contact are there. Addition of few features like adding new contact from a form, UI improvement including List View and creating and adding images or glyph Login Registration using Web API ,admin page for Staff management - add,disable,change password of staff Sync of app data on using Web API including sms history, contact, group etc and restore facility of same New Android version support including runtime permission. Support for errors, Obfuscations for app, Encryption for sensitive [login to view URL] for bugs Conditions to work on the project are 1. You have to share code, documents and special knowledge required for project with us 2. You have to help us in setting up code on our environment 3. Projects will be build using android studio. See list of work that need to be done and let us know correct estimation of time and price.