PHP / Android / iOS app enhancement

Hello We have a working mobile apps developed with the help of a freelancer. We are looking for new development resources to fix the bugs, introduce minor enhancements in the project. Streamline (consolidate) servers on to a different service provider. Tech details: Code is available in Github Private repos. Webapp: Business logic Written in CorePHP without any framework, running on Apache with SSL turned on. DB is MySQL and is hosted on a different machine and connected with SSL cert. The web app has two functionalities. Admin and end user. Both are hosted on two different machines under different domain names. Admin site needs some bug fixes and enhancements like logs, statistics, real time usage data, few third party API integrations and preventing simultaneous logins etc. It has OAuth 2.0 enabled for Facebook and G+ logins. It needs a better UI, CSS, context sensitive help, functionality steps documentation to aid users in understanding how to navigate and operate it. It also needs support chatbot to be integrated with ability to raise tickets from the apps. Mobile app UI also needs to be changed to be more user friendly and should show user activity data dashboard. Give your best quotes and references to consider for the project.